resolved

core-java-8/src/main/java/com/baeldung/hashtable/Word.java

@@ -0,0 +1,28 @@
+package com.baeldung.hashtable;
+
+public class Word {
+    private String name;
+
+    public Word(String name) {
+        this.name = name;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public boolean equals(Object o) {
+        if (o == this)
+            return true;
+        if (!(o instanceof Word))
+            return false;
+
+        Word word = (Word) o;
+        return word.getName().equals(this.name) ? true : false;
+
+    }
+
+    public int hashCode() {
+        return name.hashCode();
+    }
+}

core-java-8/src/main/java/com/baeldung/optional/OrElseAndOrElseGet.java

@@ -0,0 +1,34 @@
+package com.baeldung.optional;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.Optional;
+import java.util.Random;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class OrElseAndOrElseGet {
+
+    public static List<String> names = Arrays.asList("John", "Jones", "Kelly", "Cristina", "Raven");
+
+    private static final Logger LOG = LoggerFactory.getLogger(OrElseAndOrElseGet.class);
+
+    public String getRandomName() {
+        LOG.info("getRandomName() method - start");
+        Random random = new Random();
+        int index = random.nextInt(5);
+        LOG.info("getRandomName() method - end");
+        return names.get(index);
+    }
+
+    public String getNameUsingOrElse(String name) {
+        return Optional.ofNullable(name)
+            .orElse(getRandomName());
+    }
+
+    public String getNameUsingOrElseGet(String name) {
+        return Optional.ofNullable(name)
+            .orElseGet(() -> getRandomName());
+    }
+}

core-java-8/src/main/java/com/baeldung/optional/OrElseAndOrElseGetBenchmarkRunner.java

@@ -0,0 +1,37 @@
+package com.baeldung.optional;
+
+import java.io.IOException;
+import java.util.concurrent.TimeUnit;
+
+import org.openjdk.jmh.annotations.Benchmark;
+import org.openjdk.jmh.annotations.BenchmarkMode;
+import org.openjdk.jmh.annotations.Fork;
+import org.openjdk.jmh.annotations.Mode;
+import org.openjdk.jmh.annotations.OutputTimeUnit;
+import org.openjdk.jmh.annotations.Scope;
+import org.openjdk.jmh.annotations.State;
+import org.openjdk.jmh.runner.RunnerException;
+
+@Fork(1)
+@State(Scope.Benchmark)
+@BenchmarkMode(Mode.AverageTime)
+@OutputTimeUnit(TimeUnit.NANOSECONDS)
+public class OrElseAndOrElseGetBenchmarkRunner {
+
+    private OrElseAndOrElseGet orElsevsOrElseGet = new OrElseAndOrElseGet();
+
+    public static void main(String[] args) throws RunnerException, IOException {
+        org.openjdk.jmh.Main.main(args);
+    }
+
+    @Benchmark
+    public String orElseBenchmark() {
+        return orElsevsOrElseGet.getNameUsingOrElse("baeldung");
+    }
+
+    @Benchmark
+    public String orElseGetBenchmark() {
+        return orElsevsOrElseGet.getNameUsingOrElseGet("baeldung");
+    }
+
+}

core-java-8/src/test/java/com/baeldung/hashtable/HashtableUnitTest.java

@@ -0,0 +1,274 @@
+package com.baeldung.hashtable;
+
+import java.util.ConcurrentModificationException;
+import java.util.Enumeration;
+import java.util.Hashtable;
+import java.util.Iterator;
+import java.util.Map;
+
+import static org.junit.Assert.*;
+import static org.hamcrest.Matchers.*;
+import org.junit.Test;
+
+public class HashtableUnitTest {
+
+    @Test
+    public void whenPutAndGet_thenReturnsValue() {
+        Hashtable<Word, String> table = new Hashtable<Word, String>();
+
+        Word word = new Word("cat");
+        table.put(word, "an animal");
+
+        String definition = table.get(word);
+
+        assertEquals("an animal", definition);
+
+        definition = table.remove(word);
+
+        assertEquals("an animal", definition);
+    }
+
+    @Test
+    public void whenThesameInstanceOfKey_thenReturnsValue() {
+        Hashtable<Word, String> table = new Hashtable<Word, String>();
+        Word word = new Word("cat");
+        table.put(word, "an animal");
+        String extracted = table.get(word);
+        assertEquals("an animal", extracted);
+    }
+
+    @Test
+    public void whenEqualsOverridden_thenReturnsValue() {
+        Hashtable<Word, String> table = new Hashtable<Word, String>();
+        Word word = new Word("cat");
+        table.put(word, "an animal");
+        String extracted = table.get(new Word("cat"));
+        assertEquals("an animal", extracted);
+    }
+
+    @Test(expected = NullPointerException.class)
+    public void whenNullKey_thenException() {
+        Hashtable<Word, String> table = new Hashtable<Word, String>();
+        table.put(null, "an animal");
+    }
+
+    @Test(expected = ConcurrentModificationException.class)
+    public void whenIterate_thenFailFast() {
+
+        Hashtable<Word, String> table = new Hashtable<Word, String>();
+        table.put(new Word("cat"), "an animal");
+        table.put(new Word("dog"), "another animal");
+
+        Iterator<Word> it = table.keySet().iterator();
+        System.out.println("iterator created");
+
+        table.remove(new Word("dog"));
+        System.out.println("element removed");
+
+        while (it.hasNext()) {
+            Word key = it.next();
+            System.out.println(table.get(key));
+        }
+    }
+
+    @Test
+    public void whenEnumerate_thenNotFailFast() {
+
+        Hashtable<Word, String> table = new Hashtable<Word, String>();
+        table.put(new Word("1"), "one");
+        table.put(new Word("2"), "two");
+        table.put(new Word("3"), "three");
+        table.put(new Word("4"), "four");
+        table.put(new Word("5"), "five");
+        table.put(new Word("6"), "six");
+        table.put(new Word("7"), "seven");
+        table.put(new Word("8"), "eight");
+
+        Enumeration<Word> enumKey = table.keys();
+        System.out.println("Enumeration created");
+        table.remove(new Word("1"));
+        System.out.println("element removed");
+        while (enumKey.hasMoreElements()) {
+            Word key = enumKey.nextElement();
+            System.out.println(table.get(key));
+        }
+    }
+
+    @Test
+    public void whenAddElements_thenIterationOrderUnpredicable() {
+
+        Hashtable<Word, String> table = new Hashtable<Word, String>();
+        table.put(new Word("1"), "one");
+        table.put(new Word("2"), "two");
+        table.put(new Word("3"), "three");
+        table.put(new Word("4"), "four");
+        table.put(new Word("5"), "five");
+        table.put(new Word("6"), "six");
+        table.put(new Word("7"), "seven");
+        table.put(new Word("8"), "eight");
+
+        Iterator<Map.Entry<Word, String>> it = table.entrySet().iterator();
+        while (it.hasNext()) {
+            Map.Entry<Word, String> entry = it.next();
+            System.out.println(entry.getValue());
+        }
+    }
+
+    @Test
+    public void whenGetOrDefault_thenDefaultGot() {
+
+        Hashtable<Word, String> table = new Hashtable<Word, String>();
+        table.put(new Word("cat"), "a small domesticated carnivorous mammal");
+        Word key = new Word("dog");
+        String definition;
+
+        // old way
+        /* if (table.containsKey(key)) {
+            definition = table.get(key);
+        } else {
+            definition = "not found";
+        }*/
+
+        // new way
+        definition = table.getOrDefault(key, "not found");
+
+        assertThat(definition, is("not found"));
+    }
+
+    @Test
+    public void whenPutifAbsent_thenNotRewritten() {
+
+        Hashtable<Word, String> table = new Hashtable<Word, String>();
+        table.put(new Word("cat"), "a small domesticated carnivorous mammal");
+
+        String definition = "an animal";
+        // old way
+        /* if (!table.containsKey(new Word("cat"))) {
+            table.put(new Word("cat"), definition);
+        }*/
+        // new way
+        table.putIfAbsent(new Word("cat"), definition);
+
+        assertThat(table.get(new Word("cat")), is("a small domesticated carnivorous mammal"));
+    }
+
+    @Test
+    public void whenRemovePair_thenCheckKeyAndValue() {
+
+        Hashtable<Word, String> table = new Hashtable<Word, String>();
+        table.put(new Word("cat"), "a small domesticated carnivorous mammal");
+
+        // old way
+        /* if (table.get(new Word("cat")).equals("an animal")) {
+            table.remove(new Word("cat"));
+        }*/
+
+        // new way
+        boolean result = table.remove(new Word("cat"), "an animal");
+
+        assertThat(result, is(false));
+    }
+
+    @Test
+    public void whenReplacePair_thenValueChecked() {
+
+        Hashtable<Word, String> table = new Hashtable<Word, String>();
+        table.put(new Word("cat"), "a small domesticated carnivorous mammal");
+
+        String definition = "an animal";
+
+        // old way
+        /* if (table.containsKey(new Word("cat")) && table.get(new Word("cat")).equals("a small domesticated carnivorous mammal")) {
+            table.put(new Word("cat"), definition);
+        }*/
+        // new way
+        table.replace(new Word("cat"), "a small domesticated carnivorous mammal", definition);
+
+        assertThat(table.get(new Word("cat")), is("an animal"));
+
+    }
+
+    @Test
+    public void whenKeyIsAbsent_thenNotRewritten() {
+
+        Hashtable<Word, String> table = new Hashtable<Word, String>();
+        table.put(new Word("cat"), "a small domesticated carnivorous mammal");
+
+        // old way
+        /* if (!table.containsKey(cat)) {
+            String definition = "an animal";// calculate
+            table.put(new Word("cat"), definition);
+        }
+        */
+        // new way
+
+        table.computeIfAbsent(new Word("cat"), key -> "an animal");
+        assertThat(table.get(new Word("cat")), is("a small domesticated carnivorous mammal"));
+
+    }
+
+    @Test
+    public void whenKeyIsPresent_thenComputeIfPresent() {
+
+        Hashtable<Word, String> table = new Hashtable<Word, String>();
+        table.put(new Word("cat"), "a small domesticated carnivorous mammal");
+
+        Word cat = new Word("cat");
+        // old way
+        /* if (table.containsKey(cat)) {
+            String concatination = cat.getName() + " - " + table.get(cat);
+            table.put(cat, concatination);
+        }*/
+
+        // new way
+        table.computeIfPresent(cat, (key, value) -> key.getName() + " - " + value);
+
+        assertThat(table.get(cat), is("cat - a small domesticated carnivorous mammal"));
+
+    }
+
+    @Test
+    public void whenCompute_thenForAllKeys() {
+
+        Hashtable<String, Integer> table = new Hashtable<String, Integer>();
+        String[] animals = { "cat", "dog", "dog", "cat", "bird", "mouse", "mouse" };
+        for (String animal : animals) {
+            table.compute(animal, (key, value) -> (value == null ? Integer.valueOf(1) : Integer.valueOf(value) + 1));
+        }
+        assertThat(table.values(), hasItems(2, 2, 2, 1));
+
+    }
+
+    @Test
+    public void whenInsteadOfCompute_thenMerge() {
+
+        Hashtable<String, Integer> table = new Hashtable<String, Integer>();
+        String[] animals = { "cat", "dog", "dog", "cat", "bird", "mouse", "mouse" };
+        for (String animal : animals) {
+            table.merge(animal, 1, (oldValue, value) -> (oldValue + value));
+        }
+        assertThat(table.values(), hasItems(2, 2, 2, 1));
+    }
+
+    @Test
+    public void whenForeach_thenIterate() {
+
+        Hashtable<Word, String> table = new Hashtable<Word, String>();
+        table.put(new Word("cat"), "a small domesticated carnivorous mammal");
+        table.put(new Word("dog"), "another animal");
+        table.forEach((k, v) -> System.out.println(k.getName() + " - " + v)
+
+        );
+    }
+
+    @Test
+    public void whenReplaceall_thenNoIterationNeeded() {
+
+        Hashtable<Word, String> table = new Hashtable<Word, String>();
+        table.put(new Word("cat"), "a small domesticated carnivorous mammal");
+        table.put(new Word("dog"), "another animal");
+        table.replaceAll((k, v) -> k.getName() + " - " + v);
+
+        assertThat(table.values(), hasItems("cat - a small domesticated carnivorous mammal", "dog - another animal"));
+    }
+}

core-java-8/src/test/java/com/baeldung/java8/optional/OrElseAndOrElseGetTest.java

@@ -0,0 +1,44 @@
+package com.baeldung.java8.optional;
+
+import org.junit.Test;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import static org.junit.Assert.*;
+
+import com.baeldung.optional.OrElseAndOrElseGet;
+
+public class OrElseAndOrElseGetTest {
+
+    private OrElseAndOrElseGet orElsevsOrElseGet = new OrElseAndOrElseGet();
+
+    private static final Logger LOG = LoggerFactory.getLogger(OrElseAndOrElseGetTest.class);
+
+    @Test
+    public void givenNonEmptyOptional_whenOrElseUsed_thenGivenStringReturned() {
+        LOG.info("In givenNonEmptyOptional_whenOrElseUsed_thenGivenStringReturned()");
+        String name = orElsevsOrElseGet.getNameUsingOrElse("baeldung");
+        assertEquals(name, "baeldung");
+    }
+
+    @Test
+    public void givenEmptyOptional_whenOrElseUsed_thenRandomStringReturned() {
+        LOG.info("In givenEmptyOptional_whenOrElseUsed_thenRandomStringReturned()");
+        String name = orElsevsOrElseGet.getNameUsingOrElse(null);
+        assertTrue(orElsevsOrElseGet.names.contains(name));
+    }
+
+    @Test
+    public void givenNonEmptyOptional_whenOrElseGetUsed_thenGivenStringReturned() {
+        LOG.info("In givenNonEmptyOptional_whenOrElseGetUsed_thenGivenStringReturned()");
+        String name = orElsevsOrElseGet.getNameUsingOrElseGet("baeldung");
+        assertEquals(name, "baeldung");
+    }
+
+    @Test
+    public void givenEmptyOptional_whenOrElseGetUsed_thenRandomStringReturned() {
+        LOG.info("In givenEmptyOptional_whenOrElseGetUsed_thenRandomStringReturned()");
+        String name = orElsevsOrElseGet.getNameUsingOrElseGet(null);
+        assertTrue(orElsevsOrElseGet.names.contains(name));
+    }
+}

core-java/README.md

@@ -74,17 +74,14 @@
 - [CharSequence vs. String in Java](http://www.baeldung.com/java-char-sequence-string)
 - [Period and Duration in Java](http://www.baeldung.com/java-period-duration)
 - [Guide to the Diamond Operator in Java](http://www.baeldung.com/java-diamond-operator)
-- [Singletons in Java](http://www.baeldung.com/java-singleton)
 - [“Sneaky Throws” in Java](http://www.baeldung.com/java-sneaky-throws)
 - [OutOfMemoryError: GC Overhead Limit Exceeded](http://www.baeldung.com/java-gc-overhead-limit-exceeded)
 - [StringBuilder and StringBuffer in Java](http://www.baeldung.com/java-string-builder-string-buffer)
 - [Number of Digits in an Integer in Java](http://www.baeldung.com/java-number-of-digits-in-int)
-- [Proxy, Decorator, Adapter and Bridge Patterns](http://www.baeldung.com/java-structural-design-patterns)
 - [Creating a Java Compiler Plugin](http://www.baeldung.com/java-build-compiler-plugin)
 - [A Guide to the Static Keyword in Java](http://www.baeldung.com/java-static)
 - [Initializing Arrays in Java](http://www.baeldung.com/java-initialize-array)
 - [Guide to Java String Pool](http://www.baeldung.com/java-string-pool)
-- [Introduction to Creational Design Patterns](http://www.baeldung.com/creational-design-patterns)
 - [Quick Example - Comparator vs Comparable in Java](http://www.baeldung.com/java-comparator-comparable)
 - [Quick Guide to Java Stack](http://www.baeldung.com/java-stack)
 - [The Java continue and break Keywords](http://www.baeldung.com/java-continue-and-break)
@@ -116,8 +113,6 @@
 - [Comparing Strings in Java](http://www.baeldung.com/java-compare-strings)
 - [Guide to Inheritance in Java](http://www.baeldung.com/java-inheritance)
 - [Guide to Externalizable Interface in Java](http://www.baeldung.com/java-externalizable)
-- [The Observer Pattern in Java](http://www.baeldung.com/java-observer-pattern)
-- [Flyweight Pattern in Java](http://www.baeldung.com/java-flyweight)
 - [Object Type Casting in Java](http://www.baeldung.com/java-type-casting)
 - [A Practical Guide to DecimalFormat](http://www.baeldung.com/java-decimalformat)
 - [How to Detect the OS Using Java](http://www.baeldung.com/java-detect-os)
@@ -136,7 +131,6 @@
 - [Class Loaders in Java](http://www.baeldung.com/java-classloaders)
 - [Find Sum and Average in a Java Array](http://www.baeldung.com/java-array-sum-average)
 - [Java List UnsupportedOperationException](http://www.baeldung.com/java-list-unsupported-operation-exception)
-- [Service Locator Pattern](http://www.baeldung.com/java-service-locator-pattern)
 - [Type Erasure in Java Explained](http://www.baeldung.com/java-type-erasure)
 - [BigDecimal and BigInteger in Java](http://www.baeldung.com/java-bigdecimal-biginteger)
 - [Display All Time Zones With GMT And UTC in Java](http://www.baeldung.com/java-time-zones)
@@ -145,4 +139,5 @@
 - [Sending Emails with Java](http://www.baeldung.com/java-email)
 - [Introduction to SSL in Java](http://www.baeldung.com/java-ssl)
 - [Java KeyStore API](http://www.baeldung.com/java-keystore)
-- [Double-Checked Locking with Singleton](http://www.baeldung.com/java-singleton-double-checked-locking)
+- [Using Java Assertions](http://www.baeldung.com/java-assert)
+- [Guide to Java Clock Class](http://www.baeldung.com/java-clock)

core-java/src/main/java/com/baeldung/designpatterns/creational/abstractfactory/Color.java

@@ -1,5 +0,0 @@
-package com.baeldung.designpatterns.creational.abstractfactory;
-
-public interface Color {
-    String getColor();
-}

core-java/src/main/java/com/baeldung/designpatterns/creational/factory/Polygon.java

@@ -1,5 +0,0 @@
-package com.baeldung.designpatterns.creational.factory;
-
-public interface Polygon {
-    String getType();
-}

core-java/src/main/java/com/baeldung/nan/NaNExample.java

@@ -0,0 +1,81 @@
+package com.baeldung.nan;
+
+/**
+ * Sample usage of NaN.
+ *
+ */
+public class NaNExample {
+
+    public static void main(String[] args) {
+        NaNExample naNExample = new NaNExample();
+        naNExample.demo();
+    }
+
+    void demo() {
+        undefined_operations_produce_NaN();
+        operations_with_no_real_results_produce_NaN();
+        operations_with_NaN_produce_NaN();
+        comparison_with_NaN();
+        check_if_a_value_is_NaN();
+        assign_NaN_to_missing_values();
+    }
+
+    void undefined_operations_produce_NaN() {
+        System.out.println("Undefined Operations Produce NaN");
+        final double ZERO = 0;
+        System.out.println("ZERO / ZERO = " + (ZERO / ZERO));
+        System.out.println("INFINITY - INFINITY = " + (Double.POSITIVE_INFINITY - Double.POSITIVE_INFINITY));
+        System.out.println("INFINITY * ZERO = " + (Double.POSITIVE_INFINITY * ZERO));
+        System.out.println();
+    }
+
+    void operations_with_no_real_results_produce_NaN() {
+        System.out.println("Operations with no real results produce NaN");
+        System.out.println("SQUARE ROOT OF -1 = " + Math.sqrt(-1));
+        System.out.println("LOG OF -1 = " + Math.log(-1));
+        System.out.println();
+    }
+
+    void operations_with_NaN_produce_NaN() {
+        System.out.println("Operations with NaN produce NaN");
+        System.out.println("2 + NaN = " + (2 + Double.NaN));
+        System.out.println("2 - NaN = " + (2 - Double.NaN));
+        System.out.println("2 * NaN = " + (2 * Double.NaN));
+        System.out.println("2 / NaN = " + (2 / Double.NaN));
+        System.out.println();
+    }
+
+    void assign_NaN_to_missing_values() {
+        System.out.println("Assign NaN to Missing values");
+        double salaryRequired = Double.NaN;
+        System.out.println(salaryRequired);
+        System.out.println();
+    }
+
+    void comparison_with_NaN() {
+        System.out.println("Comparison with NaN");
+        final double NAN = Double.NaN;
+        System.out.println("NaN == 1 = " + (NAN == 1));
+        System.out.println("NaN > 1 = " + (NAN > 1));
+        System.out.println("NaN < 1 = " + (NAN < 1));
+        System.out.println("NaN != 1 = " + (NAN != 1));
+        System.out.println("NaN == NaN = " + (NAN == NAN));
+        System.out.println("NaN > NaN = " + (NAN > NAN));
+        System.out.println("NaN < NaN = " + (NAN < NAN));
+        System.out.println("NaN != NaN = " + (NAN != NAN));
+        System.out.println();
+    }
+
+    void check_if_a_value_is_NaN() {
+        System.out.println("Check if a value is NaN");
+        double x = 1;
+        System.out.println(x + " is NaN = " + (x != x));
+        System.out.println(x + " is NaN = " + (Double.isNaN(x)));
+
+        x = Double.NaN;
+        System.out.println(x + " is NaN = " + (x != x));
+        System.out.println(x + " is NaN = " + (Double.isNaN(x)));
+        System.out.println();
+    }
+
+}

core-java/src/main/java/com/baeldung/numberofdigits/NumberOfDigitsDriver.java

@@ -1,10 +1,12 @@
 package com.baeldung.numberofdigits;
 
-import static com.baeldung.designpatterns.util.LogerUtil.LOG;
+import org.apache.log4j.Logger;
 
 public class NumberOfDigitsDriver {
     private static NumberOfDigits numberOfDigits;
     
+    private static Logger LOG = Logger.getLogger(NumberOfDigitsDriver.class);
+    
     static {
         numberOfDigits = new NumberOfDigits();
     }

core-java/src/main/java/com/baeldung/scope/method/BaseMethodClass.java

@@ -0,0 +1,9 @@
+package com.baeldung.scope.method;
+
+
+public class BaseMethodClass {
+
+    public static void printMessage() {
+        System.out.println("base static method");
+    }
+}

core-java/src/main/java/com/baeldung/scope/method/ChildMethodClass.java

@@ -0,0 +1,9 @@
+package com.baeldung.scope.method;
+
+
+public class ChildMethodClass extends BaseMethodClass {
+
+    public static void printMessage() {
+        System.out.println("child static method");
+    }
+}

core-java/src/main/java/com/baeldung/scope/method/MethodHidingDemo.java

@@ -0,0 +1,8 @@
+package com.baeldung.scope.method;
+
+public class MethodHidingDemo {
+
+    public static void main(String[] args) {
+        ChildMethodClass.printMessage();
+    }
+}

core-java/src/main/java/com/baeldung/scope/variable/ChildVariable.java

@@ -0,0 +1,13 @@
+package com.baeldung.scope.variable;
+
+/**
+ * Created by Gebruiker on 5/7/2018.
+ */
+public class ChildVariable extends ParentVariable {
+
+    String instanceVariable = "child variable";
+
+    public void printInstanceVariable() {
+        System.out.println(instanceVariable);
+    }
+}

core-java/src/main/java/com/baeldung/scope/variable/HideVariable.java

@@ -0,0 +1,23 @@
+package com.baeldung.scope.variable;
+
+/**
+ * Created by Gebruiker on 5/6/2018.
+ */
+public class HideVariable {
+
+    private String message = "this is instance variable";
+
+    HideVariable() {
+        String message = "constructor local variable";
+        System.out.println(message);
+    }
+
+    public void printLocalVariable() {
+        String message = "method local variable";
+        System.out.println(message);
+    }
+
+    public void printInstanceVariable() {
+        System.out.println(this.message);
+    }
+}

core-java/src/main/java/com/baeldung/scope/variable/ParentVariable.java

@@ -0,0 +1,13 @@
+package com.baeldung.scope.variable;
+
+/**
+ * Created by Gebruiker on 5/7/2018.
+ */
+public class ParentVariable {
+
+    String instanceVariable = "parent variable";
+
+    public void printInstanceVariable() {
+        System.out.println(instanceVariable);
+    }
+}

core-java/src/main/java/com/baeldung/scope/variable/VariableHidingDemo.java

@@ -0,0 +1,18 @@
+package com.baeldung.scope.variable;
+
+/**
+ * Created by Gebruiker on 5/6/2018.
+ */
+public class VariableHidingDemo {
+    public static void main(String[] args) {
+        HideVariable variable = new HideVariable();
+        variable.printLocalVariable();
+        variable.printInstanceVariable();
+
+        ParentVariable parentVariable = new ParentVariable();
+        ParentVariable childVariable = new ChildVariable();
+
+        parentVariable.printInstanceVariable();
+        childVariable.printInstanceVariable();
+    }
+}

core-java/src/main/java/com/baeldung/stringisnumeric/Benchmarking.java

@@ -0,0 +1,75 @@
+package com.baeldung.stringisnumeric;
+
+import java.util.concurrent.TimeUnit;
+
+import org.openjdk.jmh.annotations.Benchmark;
+import org.openjdk.jmh.annotations.BenchmarkMode;
+import org.openjdk.jmh.annotations.Mode;
+import org.openjdk.jmh.annotations.OutputTimeUnit;
+import org.openjdk.jmh.annotations.Scope;
+import org.openjdk.jmh.annotations.State;
+import org.openjdk.jmh.runner.Runner;
+import org.openjdk.jmh.runner.RunnerException;
+import org.openjdk.jmh.runner.options.Options;
+import org.openjdk.jmh.runner.options.OptionsBuilder;
+
+
+public class Benchmarking {
+    public static void main(String[] args) throws RunnerException {
+        Options opt = new OptionsBuilder()
+                .include(Benchmarking.class.getSimpleName())
+                .forks(1)
+                .build();
+
+        new Runner(opt).run();
+    }
+
+    @State(Scope.Thread)
+    public static class ExecutionPlan {
+        public String number = Integer.toString(Integer.MAX_VALUE);
+        public boolean isNumber = false;
+        public IsNumeric isNumeric= new IsNumeric();
+    }
+    
+    @Benchmark 
+    @BenchmarkMode(Mode.AverageTime)
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    public void usingCoreJava(ExecutionPlan plan) {
+        plan.isNumber = plan.isNumeric.usingCoreJava(plan.number);
+    }
+    
+    @Benchmark 
+    @BenchmarkMode(Mode.AverageTime)
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    public void usingRegularExpressions(ExecutionPlan plan) {
+        plan.isNumber = plan.isNumeric.usingRegularExpressions(plan.number);
+    }
+    
+    @Benchmark 
+    @BenchmarkMode(Mode.AverageTime)
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    public void usingNumberUtils_isCreatable(ExecutionPlan plan) {
+        plan.isNumber = plan.isNumeric.usingNumberUtils_isCreatable(plan.number);
+    }
+    
+    @Benchmark 
+    @BenchmarkMode(Mode.AverageTime)
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    public void usingNumberUtils_isParsable(ExecutionPlan plan) {
+        plan.isNumber = plan.isNumeric.usingNumberUtils_isParsable(plan.number);
+    }
+    
+    @Benchmark 
+    @BenchmarkMode(Mode.AverageTime)
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    public void usingStringUtils_isNumeric(ExecutionPlan plan) {
+        plan.isNumber = plan.isNumeric.usingStringUtils_isNumeric(plan.number);
+    }
+    
+    @Benchmark 
+    @BenchmarkMode(Mode.AverageTime)
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    public void usingStringUtils_isNumericSpace(ExecutionPlan plan) {
+        plan.isNumber = plan.isNumeric.usingStringUtils_isNumericSpace(plan.number);
+    }
+}

core-java/src/main/java/com/baeldung/stringisnumeric/IsNumeric.java

@@ -0,0 +1,35 @@
+package com.baeldung.stringisnumeric;
+
+import org.apache.commons.lang3.StringUtils;
+import org.apache.commons.lang3.math.NumberUtils;
+
+public class IsNumeric {
+    public boolean usingCoreJava(String strNum) {
+        try {
+            double d = Double.parseDouble(strNum);
+        } catch (NumberFormatException | NullPointerException nfe) {
+            return false;
+        }
+        return true;
+    }
+    
+    public boolean usingRegularExpressions(String strNum) {
+        return strNum.matches("-?\\d+(\\.\\d+)?");
+    }
+    
+    public boolean usingNumberUtils_isCreatable(String strNum) {
+        return NumberUtils.isCreatable(strNum);
+    }
+    
+    public boolean usingNumberUtils_isParsable(String strNum) {
+        return NumberUtils.isParsable(strNum);
+    }
+    
+    public boolean usingStringUtils_isNumeric(String strNum) {
+        return StringUtils.isNumeric(strNum);
+    }
+    
+    public boolean usingStringUtils_isNumericSpace(String strNum) {
+        return StringUtils.isNumericSpace(strNum);
+    }
+}

core-java/src/main/java/com/baeldung/stringisnumeric/IsNumericDriver.java

@@ -0,0 +1,34 @@
+package com.baeldung.stringisnumeric;
+
+import org.apache.log4j.Logger;
+
+public class IsNumericDriver {
+    private static IsNumeric isNumeric;
+    private static Logger LOG = Logger.getLogger(IsNumericDriver.class);
+    static {
+        isNumeric =new IsNumeric();
+        
+    }
+    
+    public static void main(String[] args) {
+        LOG.info("Testing all methods...");
+        
+        boolean res = isNumeric.usingCoreJava("1001");
+        LOG.info("Using Core Java : " + res);
+        
+        res = isNumeric.usingRegularExpressions("1001");
+        LOG.info("Using Regular Expressions : " + res);
+        
+        res =isNumeric.usingNumberUtils_isCreatable("1001");
+        LOG.info("Using NumberUtils.isCreatable : " + res);
+        
+        res =isNumeric.usingNumberUtils_isParsable("1001");
+        LOG.info("Using NumberUtils.isParsable : " + res);
+        
+        res =isNumeric.usingStringUtils_isNumeric("1001");
+        LOG.info("Using StringUtils.isNumeric : " + res);
+        
+        res =isNumeric.usingStringUtils_isNumericSpace("1001");
+        LOG.info("Using StringUtils.isNumericSpace : " + res);
+    }
+}

core-java/src/test/java/com/baeldung/stringisnumeric/CoreJavaIsNumericUnitTest.java

@@ -0,0 +1,31 @@
+package com.baeldung.stringisnumeric;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.junit.Test;
+
+public class CoreJavaIsNumericUnitTest {
+    public static boolean isNumeric(String strNum) {
+        try {
+            double d = Double.parseDouble(strNum);
+        } catch (NumberFormatException | NullPointerException nfe) {
+            return false;
+        }
+        return true;
+    }
+    
+    @Test
+    public void whenUsingCoreJava_thenTrue() {
+        // Valid Numbers
+        assertThat(isNumeric("22")).isTrue();
+        assertThat(isNumeric("5.05")).isTrue();
+        assertThat(isNumeric("-200")).isTrue(); 
+        assertThat(isNumeric("10.0d")).isTrue();
+        assertThat(isNumeric("   22   ")).isTrue();
+         
+        // Invalid Numbers
+        assertThat(isNumeric(null)).isFalse();
+        assertThat(isNumeric("")).isFalse();
+        assertThat(isNumeric("abc")).isFalse();
+    }
+}

core-java/src/test/java/com/baeldung/stringisnumeric/NumberUtilsIsCreatableUnitTest.java

@@ -0,0 +1,28 @@
+package com.baeldung.stringisnumeric;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.apache.commons.lang3.math.NumberUtils;
+import org.junit.Test;
+
+public class NumberUtilsIsCreatableUnitTest {
+    @Test
+    public void givenApacheCommons_whenUsingIsParsable_thenTrue() {
+        // Valid Numbers
+        assertThat(NumberUtils.isCreatable("22")).isTrue();
+        assertThat(NumberUtils.isCreatable("5.05")).isTrue();
+        assertThat(NumberUtils.isCreatable("-200")).isTrue();
+        assertThat(NumberUtils.isCreatable("10.0d")).isTrue();
+        assertThat(NumberUtils.isCreatable("1000L")).isTrue();
+        assertThat(NumberUtils.isCreatable("0xFF")).isTrue();
+        assertThat(NumberUtils.isCreatable("07")).isTrue();
+        assertThat(NumberUtils.isCreatable("2.99e+8")).isTrue();
+         
+        // Invalid Numbers
+        assertThat(NumberUtils.isCreatable(null)).isFalse();
+        assertThat(NumberUtils.isCreatable("")).isFalse();
+        assertThat(NumberUtils.isCreatable("abc")).isFalse();
+        assertThat(NumberUtils.isCreatable(" 22 ")).isFalse();
+        assertThat(NumberUtils.isCreatable("09")).isFalse();
+    }
+}

core-java/src/test/java/com/baeldung/stringisnumeric/NumberUtilsIsParsableUnitTest.java

@@ -0,0 +1,26 @@
+package com.baeldung.stringisnumeric;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.apache.commons.lang3.math.NumberUtils;
+import org.junit.Test;
+
+public class NumberUtilsIsParsableUnitTest {
+    @Test
+    public void givenApacheCommons_whenUsingIsParsable_thenTrue() {
+        // Valid Numbers
+        assertThat(NumberUtils.isParsable("22")).isTrue();
+        assertThat(NumberUtils.isParsable("-23")).isTrue();
+        assertThat(NumberUtils.isParsable("2.2")).isTrue();
+        assertThat(NumberUtils.isParsable("09")).isTrue();
+        
+        // Invalid Numbers
+        assertThat(NumberUtils.isParsable(null)).isFalse();
+        assertThat(NumberUtils.isParsable("")).isFalse();
+        assertThat(NumberUtils.isParsable("6.2f")).isFalse();
+        assertThat(NumberUtils.isParsable("9.8d")).isFalse();
+        assertThat(NumberUtils.isParsable("22L")).isFalse();
+        assertThat(NumberUtils.isParsable("0xFF")).isFalse();
+        assertThat(NumberUtils.isParsable("2.99e+8")).isFalse();
+    }
+}

core-java/src/test/java/com/baeldung/stringisnumeric/RegularExpressionsUnitTest.java

@@ -0,0 +1,22 @@
+package com.baeldung.stringisnumeric;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.junit.Test;
+
+public class RegularExpressionsUnitTest {
+    public static boolean isNumeric(String strNum) {
+        return strNum.matches("-?\\d+(\\.\\d+)?");
+    }
+    
+    @Test
+    public void whenUsingRegularExpressions_thenTrue() {
+        // Valid Numbers
+        assertThat(isNumeric("22")).isTrue();
+        assertThat(isNumeric("5.05")).isTrue();
+        assertThat(isNumeric("-200")).isTrue();
+         
+        // Invalid Numbers
+        assertThat(isNumeric("abc")).isFalse();
+    }
+}

core-java/src/test/java/com/baeldung/stringisnumeric/StringUtilsIsNumericSpaceUnitTest.java

@@ -0,0 +1,23 @@
+package com.baeldung.stringisnumeric;
+
+import org.apache.commons.lang3.StringUtils;
+import org.junit.Test;
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class StringUtilsIsNumericSpaceUnitTest {
+    @Test
+    public void givenApacheCommons_whenUsingIsNumericSpace_thenTrue() {
+        // Valid Numbers
+        assertThat(StringUtils.isNumericSpace("123")).isTrue();
+        assertThat(StringUtils.isNumericSpace("١٢٣")).isTrue();
+        assertThat(StringUtils.isNumericSpace("")).isTrue();
+        assertThat(StringUtils.isNumericSpace("  ")).isTrue();
+        assertThat(StringUtils.isNumericSpace("12 3")).isTrue();
+         
+        // Invalid Numbers
+        assertThat(StringUtils.isNumericSpace(null)).isFalse();
+        assertThat(StringUtils.isNumericSpace("ab2c")).isFalse();
+        assertThat(StringUtils.isNumericSpace("12.3")).isFalse();
+        assertThat(StringUtils.isNumericSpace("-123")).isFalse();
+    }
+}

core-java/src/test/java/com/baeldung/stringisnumeric/StringUtilsIsNumericUnitTest.java

@@ -0,0 +1,24 @@
+package com.baeldung.stringisnumeric;
+
+import org.apache.commons.lang3.StringUtils;
+import org.junit.Test;
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class StringUtilsIsNumericUnitTest {
+    @Test
+    public void givenApacheCommons_whenUsingIsNumeric_thenTrue() {
+        // Valid Numbers
+        assertThat(StringUtils.isNumeric("123")).isTrue();
+        assertThat(StringUtils.isNumeric("١٢٣")).isTrue();
+        assertThat(StringUtils.isNumeric("१२३")).isTrue();
+         
+        // Invalid Numbers
+        assertThat(StringUtils.isNumeric(null)).isFalse();
+        assertThat(StringUtils.isNumeric("")).isFalse();
+        assertThat(StringUtils.isNumeric("  ")).isFalse();
+        assertThat(StringUtils.isNumeric("12 3")).isFalse();
+        assertThat(StringUtils.isNumeric("ab2c")).isFalse();
+        assertThat(StringUtils.isNumeric("12.3")).isFalse();
+        assertThat(StringUtils.isNumeric("-123")).isFalse();
+    }
+}

core-kotlin/pom.xml

@@ -63,6 +63,24 @@
             <artifactId>kotlinx-coroutines-core</artifactId>
             <version>${kotlinx.version}</version>
         </dependency>
+        <dependency>
+            <groupId>org.jetbrains.spek</groupId>
+            <artifactId>spek-api</artifactId>
+            <version>1.1.5</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.jetbrains.spek</groupId>
+            <artifactId>spek-subject-extension</artifactId>
+            <version>1.1.5</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.jetbrains.spek</groupId>
+            <artifactId>spek-junit-platform-engine</artifactId>
+            <version>1.1.5</version>
+            <scope>test</scope>
+        </dependency>
         <dependency>
             <groupId>com.nhaarman</groupId>
             <artifactId>mockito-kotlin</artifactId>

core-kotlin/src/test/kotlin/com/baeldung/kotlin/spek/CalculatorSubjectTest5.kt

@@ -0,0 +1,19 @@
+package com.baeldung.kotlin.spek
+
+import com.baeldung.kotlin.junit5.Calculator
+import org.jetbrains.spek.api.dsl.describe
+import org.jetbrains.spek.api.dsl.it
+import org.jetbrains.spek.subject.SubjectSpek
+import org.junit.jupiter.api.Assertions.assertEquals
+
+class CalculatorSubjectTest5 : SubjectSpek<Calculator>({
+    subject { Calculator() }
+    describe("A calculator") {
+        describe("Addition") {
+            val result = subject.add(3, 5)
+            it("Produces the correct answer") {
+                assertEquals(8, result)
+            }
+        }
+    }
+})

core-kotlin/src/test/kotlin/com/baeldung/kotlin/spek/CalculatorTest5.kt

@@ -0,0 +1,32 @@
+package com.baeldung.kotlin.spek
+
+import com.baeldung.kotlin.junit5.Calculator
+import org.jetbrains.spek.api.Spek
+import org.jetbrains.spek.api.dsl.describe
+import org.jetbrains.spek.api.dsl.given
+import org.jetbrains.spek.api.dsl.it
+import org.jetbrains.spek.api.dsl.on
+import org.junit.jupiter.api.Assertions.assertEquals
+
+class CalculatorTest5 : Spek({
+    given("A calculator") {
+        val calculator = Calculator()
+        on("Adding 3 and 5") {
+            val result = calculator.add(3, 5)
+            it("Produces 8") {
+                assertEquals(8, result)
+            }
+        }
+    }
+
+    describe("A calculator") {
+        val calculator = Calculator()
+        describe("Addition") {
+            val result = calculator.add(3, 5)
+            it("Produces the correct answer") {
+                assertEquals(8, result)
+            }
+        }
+    }
+
+})

core-kotlin/src/test/kotlin/com/baeldung/kotlin/spek/DataDrivenTest5.kt

@@ -0,0 +1,21 @@
+package com.baeldung.kotlin.spek
+
+import org.jetbrains.spek.api.Spek
+import org.jetbrains.spek.api.dsl.describe
+import org.jetbrains.spek.api.dsl.it
+import org.junit.jupiter.api.Assertions
+
+class DataDrivenTest5 : Spek({
+    describe("A data driven test") {
+        mapOf(
+                "hello" to "HELLO",
+                "world" to "WORLD"
+        ).forEach { input, expected ->
+            describe("Capitalising $input") {
+                it("Correctly returns $expected") {
+                    Assertions.assertEquals(expected, input.toUpperCase())
+                }
+            }
+        }
+    }
+})

core-kotlin/src/test/kotlin/com/baeldung/kotlin/spek/GroupTest5.kt

@@ -0,0 +1,62 @@
+package com.baeldung.kotlin.spek
+
+import org.jetbrains.spek.api.Spek
+import org.jetbrains.spek.api.dsl.describe
+import org.jetbrains.spek.api.dsl.it
+
+class GroupTest5 : Spek({
+    describe("Outer group") {
+        beforeEachTest {
+            System.out.println("BeforeEachTest 0")
+        }
+        beforeGroup {
+            System.out.println("BeforeGroup 0")
+        }
+        afterEachTest {
+            System.out.println("AfterEachTest 0")
+        }
+        afterGroup {
+            System.out.println("AfterGroup 0")
+        }
+        describe("Inner group 1") {
+            beforeEachTest {
+                System.out.println("BeforeEachTest 1")
+            }
+            beforeGroup {
+                System.out.println("BeforeGroup 1")
+            }
+            afterEachTest {
+                System.out.println("AfterEachTest 1")
+            }
+            afterGroup {
+                System.out.println("AfterGroup 1")
+            }
+            it("Test 1") {
+                System.out.println("Test 1")
+            }
+            it("Test 2") {
+                System.out.println("Test 2")
+            }
+        }
+        describe("Inner group 2") {
+            beforeEachTest {
+                System.out.println("BeforeEachTest 2")
+            }
+            beforeGroup {
+                System.out.println("BeforeGroup 2")
+            }
+            afterEachTest {
+                System.out.println("AfterEachTest 2")
+            }
+            afterGroup {
+                System.out.println("AfterGroup 2")
+            }
+            it("Test 3") {
+                System.out.println("Test 3")
+            }
+            it("Test 4") {
+                System.out.println("Test 4")
+            }
+        }
+    }
+})

flips/src/main/java/com/baeldung/flips/model/Foo.java

@@ -1,11 +1,12 @@
 package com.baeldung.flips.model;
 
 import lombok.Data;
+import lombok.NonNull;
 import lombok.RequiredArgsConstructor;
 
 @Data
 @RequiredArgsConstructor
 public class Foo {
-  private final String name;
+    @NonNull private final String name;
-  private final int id;
+    @NonNull private final int id;
 }

flips/src/test/java/com/baeldung/flips/controller/FlipControllerTest.java

@@ -20,7 +20,7 @@ import org.springframework.test.web.servlet.result.MockMvcResultMatchers;
     "first.active.after=2999-03-15T00:00:00Z",
     "logging.level.org.flips=info"
 
-})
+}, webEnvironment = SpringBootTest.WebEnvironment.MOCK)
 @AutoConfigureMockMvc
 @ActiveProfiles("dev")
 public class FlipControllerTest {

guava/pom.xml

@@ -32,6 +32,14 @@
             <version>${assertj.version}</version>
             <scope>test</scope>
         </dependency>
+
+        <!-- https://mvnrepository.com/artifact/org.hamcrest/java-hamcrest -->
+        <dependency>
+            <groupId>org.hamcrest</groupId>
+            <artifactId>java-hamcrest</artifactId>
+            <version>${java-hamcrest.version}</version>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 
     <build>
@@ -52,6 +60,7 @@
 
         <!-- testing -->
         <assertj.version>3.6.1</assertj.version>
+        <java-hamcrest.version>2.0.0.0</java-hamcrest.version>
     </properties>
 
 </project>

guava/src/test/java/org/baeldung/hamcrest/HamcrestExamplesUnitTest.java

@@ -12,6 +12,7 @@ import static org.hamcrest.Matchers.hasItems;
 import static org.hamcrest.Matchers.hasSize;
 import static org.hamcrest.Matchers.not;
 import static org.junit.Assert.assertThat;
+import static org.hamcrest.Matchers.emptyIterable;
 
 import java.util.Collections;
 import java.util.List;
@@ -57,6 +58,12 @@ public class HamcrestExamplesUnitTest {
         final List<String> collection = Lists.newArrayList();
         assertThat(collection, empty());
     }
+    
+    @Test
+    public final void givenIterableIsEmpty_whenChecking_thenEmpty() {
+        final Iterable<String> collection = Lists.newArrayList();
+        assertThat(collection, emptyIterable());
+    }
 
     @Test
     public final void givenCollectionIsNotEmpty_whenChecking_thenNotEmpty() {

hibernate5/src/main/java/com/baeldung/hibernate/HibernateUtil.java

@@ -1,30 +1,12 @@
 package com.baeldung.hibernate;
 
-import com.baeldung.hibernate.pojo.Employee;
+import com.baeldung.hibernate.pessimisticlocking.Individual;
-import com.baeldung.hibernate.pojo.EntityDescription;
+import com.baeldung.hibernate.pessimisticlocking.PessimisticLockingCourse;
-import com.baeldung.hibernate.pojo.OrderEntry;
+import com.baeldung.hibernate.pessimisticlocking.PessimisticLockingEmployee;
-import com.baeldung.hibernate.pojo.OrderEntryIdClass;
+import com.baeldung.hibernate.pessimisticlocking.PessimisticLockingStudent;
-import com.baeldung.hibernate.pojo.OrderEntryPK;
+import com.baeldung.hibernate.pojo.*;
-import com.baeldung.hibernate.pojo.PointEntity;
+import com.baeldung.hibernate.pojo.Person;
-import com.baeldung.hibernate.pojo.PolygonEntity;
+import com.baeldung.hibernate.pojo.inheritance.*;
-import com.baeldung.hibernate.pojo.Product;
-import com.baeldung.hibernate.pojo.Phone;
-import com.baeldung.hibernate.pojo.TemporalValues;
-import com.baeldung.hibernate.pojo.Course;
-import com.baeldung.hibernate.pojo.Student;
-import com.baeldung.hibernate.pojo.User;
-import com.baeldung.hibernate.pojo.UserProfile;
-import com.baeldung.hibernate.pojo.inheritance.Animal;
-import com.baeldung.hibernate.pojo.inheritance.Bag;
-import com.baeldung.hibernate.pojo.inheritance.Book;
-import com.baeldung.hibernate.pojo.inheritance.Car;
-import com.baeldung.hibernate.pojo.inheritance.MyEmployee;
-import com.baeldung.hibernate.pojo.inheritance.MyProduct;
-import com.baeldung.hibernate.pojo.inheritance.Pen;
-import com.baeldung.hibernate.pojo.inheritance.Person;
-import com.baeldung.hibernate.pojo.inheritance.Pet;
-import com.baeldung.hibernate.pojo.inheritance.Vehicle;
-
 import org.apache.commons.lang3.StringUtils;
 import org.hibernate.SessionFactory;
 import org.hibernate.boot.Metadata;
@@ -82,6 +64,12 @@ public class HibernateUtil {
         metadataSources.addAnnotatedClass(PointEntity.class);
         metadataSources.addAnnotatedClass(PolygonEntity.class);
         metadataSources.addAnnotatedClass(com.baeldung.hibernate.pojo.Person.class);
+        metadataSources.addAnnotatedClass(Individual.class);
+        metadataSources.addAnnotatedClass(PessimisticLockingEmployee.class);
+        metadataSources.addAnnotatedClass(PessimisticLockingStudent.class);
+        metadataSources.addAnnotatedClass(PessimisticLockingCourse.class);
+        metadataSources.addAnnotatedClass(com.baeldung.hibernate.pessimisticlocking.Customer.class);
+        metadataSources.addAnnotatedClass(com.baeldung.hibernate.pessimisticlocking.Address.class);
 
         Metadata metadata = metadataSources.buildMetadata();
         return metadata.getSessionFactoryBuilder()

hibernate5/src/main/java/com/baeldung/hibernate/pessimisticlocking/Address.java

@@ -0,0 +1,34 @@
+package com.baeldung.hibernate.pessimisticlocking;
+
+import javax.persistence.Embeddable;
+
+@Embeddable
+public class Address {
+
+    private String country;
+    private String city;
+
+    public Address(String country, String city) {
+        this.country = country;
+        this.city = city;
+    }
+
+    public Address() {
+    }
+
+    public String getCountry() {
+        return country;
+    }
+
+    public void setCountry(String country) {
+        this.country = country;
+    }
+
+    public String getCity() {
+        return city;
+    }
+
+    public void setCity(String city) {
+        this.city = city;
+    }
+}

hibernate5/src/main/java/com/baeldung/hibernate/pessimisticlocking/Customer.java

@@ -0,0 +1,58 @@
+package com.baeldung.hibernate.pessimisticlocking;
+
+import javax.persistence.*;
+import java.util.List;
+
+@Entity
+public class Customer {
+
+    @Id
+    private Long customerId;
+    private String name;
+    private String lastName;
+    @ElementCollection
+    @CollectionTable(name = "customer_address")
+    private List<Address> addressList;
+
+    public Customer() {
+    }
+
+    public Customer(Long customerId, String name, String lastName, List<Address> addressList) {
+        this.customerId = customerId;
+        this.name = name;
+        this.lastName = lastName;
+        this.addressList = addressList;
+    }
+
+    public Long getCustomerId() {
+        return customerId;
+    }
+
+    public void setCustomerId(Long customerId) {
+        this.customerId = customerId;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getLastName() {
+        return lastName;
+    }
+
+    public void setLastName(String lastName) {
+        this.lastName = lastName;
+    }
+
+    public List<Address> getAddressList() {
+        return addressList;
+    }
+
+    public void setAddressList(List<Address> addressList) {
+        this.addressList = addressList;
+    }
+}

hibernate5/src/main/java/com/baeldung/hibernate/pessimisticlocking/Individual.java

@@ -0,0 +1,49 @@
+package com.baeldung.hibernate.pessimisticlocking;
+
+import javax.persistence.Entity;
+import javax.persistence.Id;
+import javax.persistence.Inheritance;
+import javax.persistence.InheritanceType;
+
+@Entity
+@Inheritance(strategy = InheritanceType.JOINED)
+public class Individual {
+
+    @Id
+    private Long id;
+    private String name;
+    private String lastName;
+
+    public Individual(Long id, String name, String lastName) {
+        this.id = id;
+        this.name = name;
+        this.lastName = lastName;
+    }
+
+    public Individual() {
+    }
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getLastName() {
+        return lastName;
+    }
+
+    public void setLastName(String lastName) {
+        this.lastName = lastName;
+    }
+}

hibernate5/src/main/java/com/baeldung/hibernate/pessimisticlocking/PessimisticLockingCourse.java

@@ -0,0 +1,47 @@
+package com.baeldung.hibernate.pessimisticlocking;
+
+import javax.persistence.*;
+
+@Entity
+public class PessimisticLockingCourse {
+
+    @Id
+    private Long courseId;
+    private String name;
+    @ManyToOne
+    @JoinTable(name = "student_course")
+    private PessimisticLockingStudent student;
+
+    public PessimisticLockingCourse(Long courseId, String name, PessimisticLockingStudent student) {
+        this.courseId = courseId;
+        this.name = name;
+        this.student = student;
+    }
+
+    public PessimisticLockingCourse() {
+    }
+
+    public Long getCourseId() {
+        return courseId;
+    }
+
+    public void setCourseId(Long courseId) {
+        this.courseId = courseId;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public PessimisticLockingStudent getStudent() {
+        return student;
+    }
+
+    public void setStudent(PessimisticLockingStudent students) {
+        this.student = students;
+    }
+}

hibernate5/src/main/java/com/baeldung/hibernate/pessimisticlocking/PessimisticLockingEmployee.java

@@ -0,0 +1,27 @@
+package com.baeldung.hibernate.pessimisticlocking;
+
+import javax.persistence.Entity;
+import java.math.BigDecimal;
+
+@Entity
+public class PessimisticLockingEmployee extends Individual {
+
+    private BigDecimal salary;
+
+    public PessimisticLockingEmployee(Long id, String name, String lastName, BigDecimal salary) {
+        super(id, name, lastName);
+        this.salary = salary;
+    }
+
+    public PessimisticLockingEmployee() {
+        super();
+    }
+
+    public BigDecimal getSalary() {
+        return salary;
+    }
+
+    public void setSalary(BigDecimal average) {
+        this.salary = average;
+    }
+}

hibernate5/src/main/java/com/baeldung/hibernate/pessimisticlocking/PessimisticLockingStudent.java

@@ -0,0 +1,46 @@
+package com.baeldung.hibernate.pessimisticlocking;
+
+import javax.persistence.*;
+import java.util.List;
+
+@Entity
+public class PessimisticLockingStudent {
+
+    @Id
+    private Long id;
+    private String name;
+    @OneToMany(mappedBy = "student")
+    private List<PessimisticLockingCourse> courses;
+
+    public PessimisticLockingStudent(Long id, String name) {
+        this.id = id;
+        this.name = name;
+    }
+
+    public PessimisticLockingStudent() {
+    }
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public List<PessimisticLockingCourse> getCourses() {
+        return courses;
+    }
+
+    public void setCourses(List<PessimisticLockingCourse> courses) {
+        this.courses = courses;
+    }
+}

hibernate5/src/test/java/com/baeldung/hibernate/pessimisticlocking/BasicPessimisticLockingIntegrationTest.java

@@ -0,0 +1,151 @@
+package com.baeldung.hibernate.pessimisticlocking;
+
+import com.baeldung.hibernate.HibernateUtil;
+import com.vividsolutions.jts.util.Assert;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import javax.persistence.*;
+import java.io.IOException;
+import java.util.Arrays;
+
+public class BasicPessimisticLockingIntegrationTest {
+
+    @BeforeClass
+    public static void setUp() throws IOException {
+        EntityManager entityManager = getEntityManagerWithOpenTransaction();
+        PessimisticLockingStudent student = new PessimisticLockingStudent(1L, "JOHN");
+        PessimisticLockingCourse course = new PessimisticLockingCourse(1L, "MATH", student);
+        student.setCourses(Arrays.asList(course));
+        entityManager.persist(course);
+        entityManager.persist(student);
+        entityManager.getTransaction()
+            .commit();
+        entityManager.close();
+    }
+
+    @Test
+    public void givenFoundRecordWithPessimisticRead_whenFindingNewOne_PessimisticLockExceptionThrown() {
+        try {
+            EntityManager entityManager = getEntityManagerWithOpenTransaction();
+            entityManager.find(PessimisticLockingStudent.class, 1L, LockModeType.PESSIMISTIC_READ);
+
+            EntityManager entityManager2 = getEntityManagerWithOpenTransaction();
+            entityManager2.find(PessimisticLockingStudent.class, 1L, LockModeType.PESSIMISTIC_READ);
+
+            entityManager.close();
+            entityManager2.close();
+        } catch (Exception e) {
+            Assert.isTrue(e instanceof PessimisticLockException);
+        }
+    }
+
+    @Test
+    public void givenRecordWithPessimisticReadQuery_whenQueryingNewOne_PessimisticLockExceptionThrown() throws IOException {
+        try {
+            EntityManager entityManager = getEntityManagerWithOpenTransaction();
+            Query query = entityManager.createQuery("from Student where studentId = :studentId");
+            query.setParameter("studentId", 1L);
+            query.setLockMode(LockModeType.PESSIMISTIC_WRITE);
+            query.getResultList();
+
+            EntityManager entityManager2 = getEntityManagerWithOpenTransaction();
+            Query query2 = entityManager2.createQuery("from Student where studentId = :studentId");
+            query2.setParameter("studentId", 1L);
+            query2.setLockMode(LockModeType.PESSIMISTIC_READ);
+            query2.getResultList();
+
+            entityManager.close();
+            entityManager2.close();
+        } catch (Exception e) {
+            Assert.isTrue(e instanceof PessimisticLockException);
+        }
+    }
+
+    @Test
+    public void givenRecordWithPessimisticReadLock_whenFindingNewOne_PessimisticLockExceptionThrown() {
+        try {
+            EntityManager entityManager = getEntityManagerWithOpenTransaction();
+            PessimisticLockingStudent resultStudent = entityManager.find(PessimisticLockingStudent.class, 1L);
+            entityManager.lock(resultStudent, LockModeType.PESSIMISTIC_READ);
+
+            EntityManager entityManager2 = getEntityManagerWithOpenTransaction();
+            entityManager2.find(PessimisticLockingStudent.class, 1L, LockModeType.PESSIMISTIC_FORCE_INCREMENT);
+
+            entityManager.close();
+            entityManager2.close();
+        } catch (Exception e) {
+            Assert.isTrue(e instanceof PessimisticLockException);
+        }
+    }
+
+    @Test
+    public void givenRecordAndRefreshWithPessimisticRead_whenFindingWithPessimisticWrite_PessimisticLockExceptionThrown() {
+        try {
+            EntityManager entityManager = getEntityManagerWithOpenTransaction();
+            PessimisticLockingStudent resultStudent = entityManager.find(PessimisticLockingStudent.class, 1L);
+            entityManager.refresh(resultStudent, LockModeType.PESSIMISTIC_FORCE_INCREMENT);
+
+            EntityManager entityManager2 = getEntityManagerWithOpenTransaction();
+            entityManager2.find(PessimisticLockingStudent.class, 1L, LockModeType.PESSIMISTIC_WRITE);
+
+            entityManager.close();
+            entityManager2.close();
+        } catch (Exception e) {
+            Assert.isTrue(e instanceof PessimisticLockException);
+        }
+    }
+
+    @Test
+    public void givenRecordWithPessimisticRead_whenUpdatingRecord_PessimisticLockExceptionThrown() {
+        try {
+            EntityManager entityManager = getEntityManagerWithOpenTransaction();
+            PessimisticLockingStudent resultStudent = entityManager.find(PessimisticLockingStudent.class, 1L);
+            entityManager.refresh(resultStudent, LockModeType.PESSIMISTIC_READ);
+
+            EntityManager entityManager2 = getEntityManagerWithOpenTransaction();
+            PessimisticLockingStudent resultStudent2 = entityManager2.find(PessimisticLockingStudent.class, 1L);
+            resultStudent2.setName("Change");
+            entityManager2.persist(resultStudent2);
+            entityManager2.getTransaction()
+                .commit();
+
+            entityManager.close();
+            entityManager2.close();
+        } catch (Exception e) {
+            Assert.isTrue(e instanceof PessimisticLockException);
+        }
+    }
+
+    @Test
+    public void givenRecordWithPessimisticWrite_whenUpdatingRecord_PessimisticLockExceptionThrown() {
+        try {
+            EntityManager entityManager = getEntityManagerWithOpenTransaction();
+            PessimisticLockingStudent resultStudent = entityManager.find(PessimisticLockingStudent.class, 1L);
+            entityManager.refresh(resultStudent, LockModeType.PESSIMISTIC_WRITE);
+
+            EntityManager entityManager2 = getEntityManagerWithOpenTransaction();
+            PessimisticLockingStudent resultStudent2 = entityManager2.find(PessimisticLockingStudent.class, 1L);
+            resultStudent2.setName("Change");
+            entityManager2.persist(resultStudent2);
+            entityManager2.getTransaction()
+                .commit();
+
+            entityManager.close();
+            entityManager2.close();
+        } catch (Exception e) {
+            Assert.isTrue(e instanceof PessimisticLockException);
+        }
+    }
+
+    protected static EntityManager getEntityManagerWithOpenTransaction() throws IOException {
+        String propertyFileName = "hibernate-pessimistic-locking.properties";
+        EntityManager entityManager = HibernateUtil.getSessionFactory(propertyFileName)
+            .openSession();
+        entityManager.getTransaction()
+            .begin();
+
+        return entityManager;
+    }
+
+}

hibernate5/src/test/java/com/baeldung/hibernate/pessimisticlocking/PessimisticLockScopesIntegrationTest.java

@@ -0,0 +1,115 @@
+package com.baeldung.hibernate.pessimisticlocking;
+
+import com.baeldung.hibernate.HibernateUtil;
+import org.junit.Test;
+
+import javax.persistence.EntityManager;
+import javax.persistence.LockModeType;
+import javax.persistence.PessimisticLockScope;
+import java.io.IOException;
+import java.math.BigDecimal;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.Map;
+
+public class PessimisticLockScopesIntegrationTest {
+
+    @Test
+    public void givenEclipseEntityWithJoinInheritance_whenNormalLock_thenShouldChildAndParentEntity() throws IOException {
+        EntityManager em = getEntityManagerWithOpenTransaction();
+        PessimisticLockingEmployee employee = new PessimisticLockingEmployee(1L, "JOHN", "SMITH", new BigDecimal(4.5));
+        em.persist(employee);
+        em.getTransaction()
+            .commit();
+        em.close();
+
+        // NORMAL SCOPE
+        EntityManager em2 = getEntityManagerWithOpenTransaction();
+        PessimisticLockingEmployee foundEmployee = em2.find(PessimisticLockingEmployee.class, 1L, LockModeType.PESSIMISTIC_WRITE);
+        em2.getTransaction()
+            .rollback();
+
+        // EXTENDED SCOPE
+        Map<String, Object> map = new HashMap<>();
+        map.put("javax.persistence.lock.scope", PessimisticLockScope.EXTENDED);
+
+        EntityManager em3 = getEntityManagerWithOpenTransaction();
+        foundEmployee = em3.find(PessimisticLockingEmployee.class, 1L, LockModeType.PESSIMISTIC_WRITE, map);
+        em3.getTransaction()
+            .rollback();
+
+        em2.close();
+        em3.close();
+    }
+
+    @Test
+    public void givenEntityWithElementCollection_whenLock_thenHibernateExtendedScopeLockOnlyOwningEntity() throws IOException {
+        EntityManager em = getEntityManagerWithOpenTransaction();
+        Address address = new Address("Poland", "Warsaw");
+        Customer customer = new Customer(1L, "JOE", "DOE", Arrays.asList(address));
+        em.persist(customer);
+        em.getTransaction()
+            .commit();
+        em.close();
+
+        // NORMAL SCOPE
+        EntityManager em2 = getEntityManagerWithOpenTransaction();
+        Customer foundCustomer = em2.find(Customer.class, 1L, LockModeType.PESSIMISTIC_WRITE);
+        em2.getTransaction()
+            .rollback();
+
+        // EXTENDED SCOPE
+        Map<String, Object> map = new HashMap<>();
+        map.put("javax.persistence.lock.scope", PessimisticLockScope.EXTENDED);
+
+        EntityManager em3 = getEntityManagerWithOpenTransaction();
+        foundCustomer = em3.find(Customer.class, 1L, LockModeType.PESSIMISTIC_WRITE, map);
+        em2.getTransaction()
+            .rollback();
+
+        em2.close();
+        em3.close();
+    }
+
+    @Test
+    public void givenEntityWithOneToMany_whenLock_thenHibernateExtendedScopeLockOnlyOwningEntity() throws IOException {
+        EntityManager em = getEntityManagerWithOpenTransaction();
+        PessimisticLockingStudent student = new PessimisticLockingStudent(1L, "JOE");
+        PessimisticLockingCourse course = new PessimisticLockingCourse(1L, "COURSE", student);
+        student.setCourses(Arrays.asList(course));
+        em.persist(course);
+        em.persist(student);
+        em.getTransaction()
+            .commit();
+        em.close();
+
+        // NORMAL SCOPE
+        EntityManager em2 = getEntityManagerWithOpenTransaction();
+        PessimisticLockingCourse foundCourse = em2.find(PessimisticLockingCourse.class, 1L, LockModeType.PESSIMISTIC_WRITE);
+        em2.getTransaction()
+            .rollback();
+
+        // EXTENDED SCOPE
+        Map<String, Object> map = new HashMap<>();
+        map.put("javax.persistence.lock.scope", PessimisticLockScope.EXTENDED);
+
+        EntityManager em3 = getEntityManagerWithOpenTransaction();
+        foundCourse = em3.find(PessimisticLockingCourse.class, 1L, LockModeType.PESSIMISTIC_WRITE, map);
+        em3.getTransaction()
+            .rollback();
+
+        em2.close();
+        em3.close();
+    }
+
+    protected EntityManager getEntityManagerWithOpenTransaction() throws IOException {
+        String propertyFileName = "hibernate-pessimistic-locking.properties";
+        EntityManager entityManager = HibernateUtil.getSessionFactory(propertyFileName)
+            .openSession();
+        entityManager.getTransaction()
+            .begin();
+
+        return entityManager;
+    }
+
+}

hibernate5/src/test/resources/hibernate-pessimistic-locking.properties

@@ -0,0 +1,8 @@
+hibernate.connection.driver_class=org.h2.Driver
+hibernate.connection.url=jdbc:h2:mem:mydb1;DB_CLOSE_DELAY=-1;LOCK_TIMEOUT=100;MVCC=FALSE
+hibernate.connection.username=sa
+hibernate.connection.autocommit=true
+hibernate.dialect=org.hibernate.dialect.H2Dialect
+
+hibernate.show_sql=true
+hibernate.hbm2ddl.auto=create-drop

httpclient/src/test/java/org/baeldung/httpclient/sec/HttpClientAuthLiveTest.java

@@ -24,6 +24,7 @@ import org.junit.Test;
 
 import java.io.IOException;
 import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
 
 import static org.hamcrest.Matchers.equalTo;
 import static org.junit.Assert.assertThat;
@@ -89,7 +90,7 @@ public class HttpClientAuthLiveTest {
     public final void givenAuthorizationHeaderIsSetManually_whenExecutingGetRequest_thenSuccess2() throws IOException {
         final HttpGet request = new HttpGet(URL_SECURED_BY_BASIC_AUTHENTICATION);
         final String auth = DEFAULT_USER + ":" + DEFAULT_PASS;
-        final byte[] encodedAuth = Base64.encodeBase64(auth.getBytes(Charset.forName("ISO-8859-1")));
+        final byte[] encodedAuth = Base64.encodeBase64(auth.getBytes(StandardCharsets.ISO_8859_1));
         final String authHeader = "Basic " + new String(encodedAuth);
         request.setHeader(HttpHeaders.AUTHORIZATION, authHeader);
 
@@ -129,7 +130,7 @@ public class HttpClientAuthLiveTest {
 
     private String authorizationHeader(final String username, final String password) {
         final String auth = username + ":" + password;
-        final byte[] encodedAuth = Base64.encodeBase64(auth.getBytes(Charset.forName("ISO-8859-1")));
+        final byte[] encodedAuth = Base64.encodeBase64(auth.getBytes(StandardCharsets.ISO_8859_1));
 
         return "Basic " + new String(encodedAuth);
     }

javax-servlets/pom.xml

@@ -1,4 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
+<<<<<<< HEAD
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
 	<modelVersion>4.0.0</modelVersion>
@@ -75,5 +76,79 @@
 		<org.apache.httpcomponents.version>4.5.3</org.apache.httpcomponents.version>
 		<spring-test.version>5.0.5.RELEASE</spring-test.version>
 	</properties>
+=======
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <artifactId>javax-servlets</artifactId>
+  <version>1.0-SNAPSHOT</version>
+
+  <parent>
+    <groupId>com.baeldung</groupId>
+    <artifactId>parent-modules</artifactId>
+    <version>1.0.0-SNAPSHOT</version>
+  </parent>
+
+  <dependencies>
+    <!-- File Uploading -->
+    <dependency>
+      <groupId>commons-fileupload</groupId>
+      <artifactId>commons-fileupload</artifactId>
+      <version>1.3.3</version>
+    </dependency>
+    <dependency>
+      <groupId>commons-io</groupId>
+      <artifactId>commons-io</artifactId>
+      <version>2.6</version>
+    </dependency>
+
+    <!-- Servlet -->
+    <dependency>
+      <groupId>javax.servlet</groupId>
+      <artifactId>javax.servlet-api</artifactId>
+      <version>4.0.1</version>
+    </dependency>
+    <dependency>
+      <groupId>javax.servlet.jsp.jstl</groupId>
+      <artifactId>jstl-api</artifactId>
+      <version>1.2</version>
+    </dependency>
+    <dependency>
+      <groupId>javax.servlet.jsp</groupId>
+      <artifactId>javax.servlet.jsp-api</artifactId>
+      <version>2.3.1</version>
+    </dependency>
+    <dependency>
+      <groupId>javax.servlet</groupId>
+      <artifactId>jstl</artifactId>
+      <version>1.2</version>
+    </dependency>
+
+    <dependency>
+      <groupId>org.apache.httpcomponents</groupId>
+      <artifactId>httpclient</artifactId>
+      <version>${org.apache.httpcomponents.version}</version>
+      <scope>test</scope>
+      <exclusions>
+        <exclusion>
+          <artifactId>commons-logging</artifactId>
+          <groupId>commons-logging</groupId>
+        </exclusion>
+      </exclusions>
+    </dependency>
+    <dependency>
+      <groupId>org.springframework</groupId>
+      <artifactId>spring-test</artifactId>
+      <version>${spring-test.version}</version>
+      <scope>test</scope>
+    </dependency>
+  </dependencies>
+
+  <properties>
+    <org.apache.httpcomponents.version>4.5.3</org.apache.httpcomponents.version>
+    <spring-test.version>5.0.5.RELEASE</spring-test.version>
+  </properties>
+>>>>>>> c2590b9d7ed2068984a248e213046f0cf34bdc30
 
 </project>

javax-servlets/src/main/java/com/baeldung/Constants.java

@@ -0,0 +1,11 @@
+package com.baeldung;
+
+public class Constants {
+
+  public static final String UPLOAD_DIRECTORY = "upload";
+  public static final String DEFAULT_FILENAME = "default.file";
+
+  public static final int MEMORY_THRESHOLD = 1024 * 1024 * 3;
+  public static final int MAX_FILE_SIZE = 1024 * 1024 * 40;
+  public static final int MAX_REQUEST_SIZE = 1024 * 1024 * 50;
+}

javax-servlets/src/main/java/com/baeldung/servlets/MultipartServlet.java

@@ -0,0 +1,54 @@
+package com.baeldung.servlets;
+
+import com.baeldung.Constants;
+
+import javax.servlet.ServletException;
+import javax.servlet.annotation.MultipartConfig;
+import javax.servlet.annotation.WebServlet;
+import javax.servlet.http.HttpServlet;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import javax.servlet.http.Part;
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+
+import static com.baeldung.Constants.UPLOAD_DIRECTORY;
+
+@WebServlet(
+    name = "MultiPartServlet",
+    urlPatterns = {"/multiPartServlet"}
+)
+@MultipartConfig(fileSizeThreshold = 1024 * 1024, maxFileSize = 1024 * 1024 * 5, maxRequestSize = 1024 * 1024 * 5 * 5)
+public class MultipartServlet extends HttpServlet {
+
+    private static final long serialVersionUID = 1L;
+
+    private String getFileName(Part part) {
+        for (String content : part.getHeader("content-disposition").split(";")) {
+            if (content.trim().startsWith("filename"))
+                return content.substring(content.indexOf("=") + 2, content.length() - 1);
+        }
+        return Constants.DEFAULT_FILENAME;
+    }
+
+    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
+
+        String uploadPath = getServletContext().getRealPath("") + File.separator + UPLOAD_DIRECTORY;
+        File uploadDir = new File(uploadPath);
+        if (!uploadDir.exists())
+            uploadDir.mkdir();
+
+        try {
+            String fileName = "";
+            for (Part part : request.getParts()) {
+                fileName = getFileName(part);
+                part.write(uploadPath + File.separator + fileName);
+            }
+            request.setAttribute("message", "File " + fileName + " has uploaded successfully!");
+        } catch (FileNotFoundException fne) {
+            request.setAttribute("message", "There was an error: " + fne.getMessage());
+        }
+        getServletContext().getRequestDispatcher("/result.jsp").forward(request, response);
+    }
+}

javax-servlets/src/main/java/com/baeldung/servlets/UploadServlet.java

@@ -0,0 +1,63 @@
+package com.baeldung.servlets;
+
+import javax.servlet.annotation.WebServlet;
+import org.apache.commons.fileupload.FileItem;
+import org.apache.commons.fileupload.disk.DiskFileItemFactory;
+import org.apache.commons.fileupload.servlet.ServletFileUpload;
+
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServlet;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import java.io.File;
+import java.io.IOException;
+import java.util.List;
+
+import static com.baeldung.Constants.*;
+
+@WebServlet(
+    name = "UploadServlet",
+    urlPatterns = {"/uploadFile"}
+)
+public class UploadServlet extends HttpServlet {
+
+    private static final long serialVersionUID = 1L;
+
+    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
+
+        if (ServletFileUpload.isMultipartContent(request)) {
+
+            DiskFileItemFactory factory = new DiskFileItemFactory();
+            factory.setSizeThreshold(MEMORY_THRESHOLD);
+            factory.setRepository(new File(System.getProperty("java.io.tmpdir")));
+
+            ServletFileUpload upload = new ServletFileUpload(factory);
+            upload.setFileSizeMax(MAX_FILE_SIZE);
+            upload.setSizeMax(MAX_REQUEST_SIZE);
+            String uploadPath = getServletContext().getRealPath("") + File.separator + UPLOAD_DIRECTORY;
+            File uploadDir = new File(uploadPath);
+            if (!uploadDir.exists()) {
+                uploadDir.mkdir();
+            }
+
+            try {
+                List<FileItem> formItems = upload.parseRequest(request);
+
+                if (formItems != null && formItems.size() > 0) {
+                    for (FileItem item : formItems) {
+                        if (!item.isFormField()) {
+                            String fileName = new File(item.getName()).getName();
+                            String filePath = uploadPath + File.separator + fileName;
+                            File storeFile = new File(filePath);
+                            item.write(storeFile);
+                            request.setAttribute("message", "File " + fileName + " has uploaded successfully!");
+                        }
+                    }
+                }
+            } catch (Exception ex) {
+                request.setAttribute("message", "There was an error: " + ex.getMessage());
+            }
+            getServletContext().getRequestDispatcher("/result.jsp").forward(request, response);
+        }
+    }
+}

javax-servlets/src/main/java/com/baeldung/servlets/UploadWelcomeServlet.java

@@ -0,0 +1,18 @@
+package com.baeldung.servlets;
+
+import java.io.IOException;
+import javax.servlet.ServletException;
+import javax.servlet.annotation.WebServlet;
+import javax.servlet.http.HttpServlet;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+
+@WebServlet(name = "UploadWelcomeServlet", urlPatterns = "/uploadwelcome")
+public class UploadWelcomeServlet extends HttpServlet {
+
+  @Override
+  protected void doGet(HttpServletRequest request, HttpServletResponse response)
+      throws ServletException, IOException {
+    request.getRequestDispatcher("/upload.jsp").forward(request, response);
+  }
+}

javax-servlets/src/main/webapp/WEB-INF/web.xml

@@ -1,7 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
-         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
-         version="3.1">
-
-</web-app>

javax-servlets/src/main/webapp/result.jsp

@@ -0,0 +1,13 @@
+<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
+<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
+<html>
+
+<head>
+    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
+    <title>Upload Result</title>
+</head>
+
+<body>
+    <h2>${message}</h2>
+</body>
+</html>

javax-servlets/src/main/webapp/upload.jsp

@@ -0,0 +1,23 @@
+<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" %>
+<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
+<html>
+
+<head>
+    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
+    <title>File Upload Demo</title>
+</head>
+
+<body>
+    <div>Apache FileUpload</div>
+    <form method="post" action="uploadFile" enctype="multipart/form-data">
+        Choose a file: <input type="file" name="uploadFile"/><input type="submit" value="Upload"/>
+    </form>
+
+    </br>
+
+    <div>Servlet Multipart</div>
+    <form method="post" action="multiPartServlet" enctype="multipart/form-data">
+        Choose a file: <input type="file" name="multiPartServlet"/><input type="submit" value="Upload"/>
+    </form>
+</body>
+</html>

jni/pom.xml

@@ -0,0 +1,15 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <groupId>com.baeldung</groupId>
+  <artifactId>jni</artifactId>
+  <version>0.0.1-SNAPSHOT</version>
+  
+  <dependencies>
+    <dependency>
+        <groupId>junit</groupId>
+        <artifactId>junit</artifactId>
+        <version>4.8.1</version>
+        <scope>test</scope>
+    </dependency>
+  </dependencies>
+</project>

jni/src/main/cpp/com_baeldung_jni_ExampleObjectsJNI.cpp

@@ -0,0 +1,48 @@
+#include "com_baeldung_jni_ExampleObjectsJNI.h"
+#include <iostream>
+
+/*
+ * Class:     com_baeldung_jni_ExampleObjectsJNI
+ * Method:    createUser
+ * Signature: (Ljava/lang/String;D)Lcom/baeldung/jni/UserData;
+ */
+JNIEXPORT jobject JNICALL Java_com_baeldung_jni_ExampleObjectsJNI_createUser
+  (JNIEnv *env, jobject thisObject, jstring name, jdouble balance){
+  
+    // Create the object of the class UserData
+    jclass userDataClass = env->FindClass("com/baeldung/jni/UserData");
+    jobject newUserData = env->AllocObject(userDataClass);
+	
+    // Get UserData fields to set
+    jfieldID nameField = env->GetFieldID(userDataClass , "name", "Ljava/lang/String;");
+    jfieldID balanceField = env->GetFieldID(userDataClass , "balance", "D");
+	
+    // Set the values of the new object
+    env->SetObjectField(newUserData, nameField, name);
+    env->SetDoubleField(newUserData, balanceField, balance);
+    
+    // Return the created object
+    return newUserData;
+  }
+
+/*
+ * Class:     com_baeldung_jni_ExampleObjectsJNI
+ * Method:    printUserData
+ * Signature: (Lcom/baeldung/jni/UserData;)Ljava/lang/String;
+ */
+JNIEXPORT jstring JNICALL Java_com_baeldung_jni_ExampleObjectsJNI_printUserData
+  (JNIEnv *env, jobject thisObject, jobject userData){
+  	
+  	// Find the class method id
+  	jclass userDataClass = env->GetObjectClass(userData);
+  	jmethodID methodId = env->GetMethodID(userDataClass, "getUserInfo", "()Ljava/lang/String;");
+
+    // Call the object method and get the result
+    jstring result = (jstring)env->CallObjectMethod(userData, methodId);
+	
+    // Print the result
+    std::cout << "C++: User data is: " << env->GetStringUTFChars(result, NULL) << std::endl;
+    
+    return result;
+  }
+

jni/src/main/cpp/com_baeldung_jni_ExampleObjectsJNI.h

@@ -0,0 +1,29 @@
+/* DO NOT EDIT THIS FILE - it is machine generated */
+#include <jni.h>
+/* Header for class com_baeldung_jni_ExampleObjectsJNI */
+
+#ifndef _Included_com_baeldung_jni_ExampleObjectsJNI
+#define _Included_com_baeldung_jni_ExampleObjectsJNI
+#ifdef __cplusplus
+extern "C" {
+#endif
+/*
+ * Class:     com_baeldung_jni_ExampleObjectsJNI
+ * Method:    createUser
+ * Signature: (Ljava/lang/String;D)Lcom/baeldung/jni/UserData;
+ */
+JNIEXPORT jobject JNICALL Java_com_baeldung_jni_ExampleObjectsJNI_createUser
+  (JNIEnv *, jobject, jstring, jdouble);
+
+/*
+ * Class:     com_baeldung_jni_ExampleObjectsJNI
+ * Method:    printUserData
+ * Signature: (Lcom/baeldung/jni/UserData;)V
+ */
+JNIEXPORT jstring JNICALL Java_com_baeldung_jni_ExampleObjectsJNI_printUserData
+  (JNIEnv *, jobject, jobject);
+
+#ifdef __cplusplus
+}
+#endif
+#endif

jni/src/main/cpp/com_baeldung_jni_ExampleParametersJNI.cpp

@@ -0,0 +1,34 @@
+#include "com_baeldung_jni_ExampleParametersJNI.h"
+#include <iostream>
+#include <string>
+
+/*
+ * Class:     com_baeldung_jni_ExampleParametersJNI
+ * Method:    sumIntegers
+ * Signature: (II)J
+ */
+JNIEXPORT jlong JNICALL Java_com_baeldung_jni_ExampleParametersJNI_sumIntegers (JNIEnv* env, jobject thisObject, jint first, jint second){
+    std::cout << "C++: The numbers received are : " << first << " and " << second << std::endl;
+    return (long)first + (long)second;
+}
+
+
+/*
+ * Class:     com_baeldung_jni_ExampleParametersJNI
+ * Method:    sayHelloToMe
+ * Signature: (Ljava/lang/String;Z)Ljava/lang/String;
+ */
+JNIEXPORT jstring JNICALL Java_com_baeldung_jni_ExampleParametersJNI_sayHelloToMe (JNIEnv* env, jobject thisObject, jstring name, jboolean isFemale){
+    const char* nameCharPointer = env->GetStringUTFChars(name, NULL);
+    std::cout << "C++: The string received is: " << nameCharPointer << std::endl;
+    std::string title;
+    if(isFemale){
+        title = "Ms. ";
+    }
+    else{
+        title = "Mr. ";
+    }
+
+    std::string fullName = title + nameCharPointer;
+    return env->NewStringUTF(fullName.c_str());
+}

jni/src/main/cpp/com_baeldung_jni_ExampleParametersJNI.h

@@ -0,0 +1,29 @@
+/* DO NOT EDIT THIS FILE - it is machine generated */
+#include <jni.h>
+/* Header for class com_baeldung_jni_ExampleParametersJNI */
+
+#ifndef _Included_com_baeldung_jni_ExampleParametersJNI
+#define _Included_com_baeldung_jni_ExampleParametersJNI
+#ifdef __cplusplus
+extern "C" {
+#endif
+/*
+ * Class:     com_baeldung_jni_ExampleParametersJNI
+ * Method:    sumIntegers
+ * Signature: (II)J
+ */
+JNIEXPORT jlong JNICALL Java_com_baeldung_jni_ExampleParametersJNI_sumIntegers
+  (JNIEnv*, jobject, jint, jint);
+
+/*
+ * Class:     com_baeldung_jni_ExampleParametersJNI
+ * Method:    sayHelloToMe
+ * Signature: (Ljava/lang/String;Z)Ljava/lang/String;
+ */
+JNIEXPORT jstring JNICALL Java_com_baeldung_jni_ExampleParametersJNI_sayHelloToMe
+  (JNIEnv*, jobject, jstring, jboolean);
+
+#ifdef __cplusplus
+}
+#endif
+#endif

jni/src/main/cpp/com_baeldung_jni_HelloWorldJNI.cpp

@@ -0,0 +1,13 @@
+#include "com_baeldung_jni_HelloWorldJNI.h"
+#include <iostream>
+
+/*
+ * Class:     com_baeldung_jni_HelloWorldJNI
+ * Method:    sayHello
+ * Signature: ()Ljava/lang/String;
+ */
+JNIEXPORT jstring JNICALL Java_com_baeldung_jni_HelloWorldJNI_sayHello (JNIEnv* env, jobject thisObject) {
+	std::string hello = "Hello from C++ !!";
+    std::cout << hello << std::endl;
+    return env->NewStringUTF(hello.c_str());
+}

jni/src/main/cpp/com_baeldung_jni_HelloWorldJNI.h

@@ -0,0 +1,21 @@
+/* DO NOT EDIT THIS FILE - it is machine generated */
+#include <jni.h>
+/* Header for class com_baeldung_jni_HelloWorldJNI */
+
+#ifndef _Included_com_baeldung_jni_HelloWorldJNI
+#define _Included_com_baeldung_jni_HelloWorldJNI
+#ifdef __cplusplus
+extern "C" {
+#endif
+/*
+ * Class:     com_baeldung_jni_HelloWorldJNI
+ * Method:    sayHello
+ * Signature: ()V
+ */
+JNIEXPORT jstring JNICALL Java_com_baeldung_jni_HelloWorldJNI_sayHello
+  (JNIEnv *, jobject);
+
+#ifdef __cplusplus
+}
+#endif
+#endif

jni/src/main/cpp/generateNativeLib.bat

@@ -0,0 +1,6 @@
+REM Create the header with javac -h . ClassName.java
+REM Remember to set your JAVA_HOME env var
+g++ -c -I%JAVA_HOME%\include -I%JAVA_HOME%\include\win32 com_baeldung_jni_HelloWorldJNI.cpp -o com_baeldung_jni_HelloWorldJNI.o
+g++ -c -I%JAVA_HOME%\include -I%JAVA_HOME%\include\win32 com_baeldung_jni_ExampleParametersJNI.cpp -o com_baeldung_jni_ExampleParametersJNI.o
+g++ -c -I%JAVA_HOME%\include -I%JAVA_HOME%\include\win32 com_baeldung_jni_ExampleObjectsJNI.cpp -o com_baeldung_jni_ExampleObjectsJNI.o
+g++ -shared -o ..\..\..\native\win32\native.dll com_baeldung_jni_HelloWorldJNI.o com_baeldung_jni_ExampleParametersJNI.o com_baeldung_jni_ExampleObjectsJNI.o -Wl,--add-stdcall-alias

jni/src/main/cpp/generateNativeLib.sh

@@ -0,0 +1,7 @@
+# Create the header with javac -h . ClassName.java
+# Remember to set your JAVA_HOME env var
+g++ -c -fPIC -I${JAVA_HOME}/include -I${JAVA_HOME}/include/linux com_baeldung_jni_HelloWorldJNI.cpp -o com_baeldung_jni_HelloWorldJNI.o
+g++ -c -fPIC -I${JAVA_HOME}/include -I${JAVA_HOME}/include/linux com_baeldung_jni_ExampleParametersJNI.cpp -o com_baeldung_jni_ExampleParametersJNI.o
+g++ -c -fPIC -I${JAVA_HOME}/include -I${JAVA_HOME}/include/linux com_baeldung_jni_ExampleObjectsJNI.cpp -o com_baeldung_jni_ExampleObjectsJNI.o
+g++ -shared -fPIC -o ../../../native/linux_x86_64/libnative.so com_baeldung_jni_HelloWorldJNI.o com_baeldung_jni_ExampleParametersJNI.o com_baeldung_jni_ExampleObjectsJNI.o -lc
+# Don't forget to set java.library.path to point to the folder where you have the libnative you're loading.

jni/src/main/cpp/generateNativeLibMac.sh

@@ -0,0 +1,6 @@
+# Create the header with javac -h . ClassName.java
+# Remember to set your JAVA_HOME env var
+g++ -c -fPIC -I${JAVA_HOME}/include -I${JAVA_HOME}/include/darwin com_baeldung_jni_HelloWorldJNI.cpp -o com_baeldung_jni_HelloWorldJNI.o
+g++ -c -fPIC -I${JAVA_HOME}/include -I${JAVA_HOME}/include/darwin com_baeldung_jni_ExampleParametersJNI.cpp -o com_baeldung_jni_ExampleParametersJNI.o
+g++ -c -fPIC -I${JAVA_HOME}/include -I${JAVA_HOME}/include/darwin com_baeldung_jni_ExampleObjectsJNI.cpp -o com_baeldung_jni_ExampleObjectsJNI.o
+g++ -dynamiclib -o ../../../native/macos/libnative.dylib com_baeldung_jni_HelloWorldJNI.o com_baeldung_jni_ExampleParametersJNI.o com_baeldung_jni_ExampleObjectsJNI.o -lc

jni/src/main/java/com/baeldung/jni/ExampleObjectsJNI.java

@@ -0,0 +1,19 @@
+package com.baeldung.jni;
+
+public class ExampleObjectsJNI {
+
+    static {
+        System.loadLibrary("native");
+    }
+    
+    public static void main(String[] args) {
+        ExampleObjectsJNI instance = new ExampleObjectsJNI();
+        UserData newUser = instance.createUser("John Doe", 450.67);
+        instance.printUserData(newUser);
+    }
+    
+    public native UserData createUser(String name, double balance);
+    
+    public native String printUserData(UserData user);
+
+}

jni/src/main/java/com/baeldung/jni/ExampleParametersJNI.java

@@ -0,0 +1,20 @@
+package com.baeldung.jni;
+
+public class ExampleParametersJNI {
+
+    static {
+        System.loadLibrary("native");
+    }
+    
+    public static void main(String[] args) {  
+        System.out.println("Java: My full name: " + new ExampleParametersJNI().sayHelloToMe("Martin", false));
+        long sumFromNative = new ExampleParametersJNI().sumIntegers(456, 44);
+        System.out.println("Java: The sum coming from native code is: " + sumFromNative);
+    }
+    
+    // Declare another method sumIntegers that receives two integers and return a long with the sum
+    public native long sumIntegers(int first, int second);
+    
+    // Declare another method sayHelloToMe that receives the name and gender and returns the proper salutation
+    public native String sayHelloToMe(String name, boolean isFemale);
+}

jni/src/main/java/com/baeldung/jni/HelloWorldJNI.java

@@ -0,0 +1,15 @@
+package com.baeldung.jni;
+
+public class HelloWorldJNI {
+
+    static {
+        System.loadLibrary("native");
+    }
+    
+    public static void main(String[] args) {
+        new HelloWorldJNI().sayHello();
+    }
+
+    // Declare a native method sayHello() that receives no arguments and returns void
+    public native String sayHello();
+}

jni/src/main/java/com/baeldung/jni/UserData.java

@@ -0,0 +1,11 @@
+package com.baeldung.jni;
+
+public class UserData {
+    
+    public String name;
+    public double balance;
+    
+    public String getUserInfo() {
+        return "[name]=" + name + ", [balance]=" + balance;
+    }
+}

jni/src/test/java/com/baeldung/jni/JNINativeTests.java

@@ -0,0 +1,58 @@
+package com.baeldung.jni;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+
+import org.junit.Before;
+import org.junit.Test;
+
+public class JNINativeTests {
+    
+    @Before
+    public void setup() {
+        System.loadLibrary("native");
+    }
+    
+    @Test
+    public void whenNativeHelloWorld_thenOutputIsAsExpected() {
+        HelloWorldJNI helloWorld = new HelloWorldJNI();
+        String helloFromNative = helloWorld.sayHello();
+        assertTrue(!helloFromNative.isEmpty() && helloFromNative.equals("Hello from C++ !!"));
+    }
+    
+    @Test
+    public void whenSumNative_thenResultIsArithmeticallyCorrect() {
+        ExampleParametersJNI parametersNativeMethods = new ExampleParametersJNI();
+        assertTrue(parametersNativeMethods.sumIntegers(200, 400) == 600L);
+    }
+    
+    @Test
+    public void whenSayingNativeHelloToMe_thenResultIsAsExpected() {
+        ExampleParametersJNI parametersNativeMethods = new ExampleParametersJNI();
+        assertEquals(parametersNativeMethods.sayHelloToMe("Orange", true), "Ms. Orange");
+    }
+
+    @Test
+    public void whenCreatingNativeObject_thenObjectIsNotNullAndHasCorrectData() {
+        String name = "Iker Casillas";
+        double balance = 2378.78;
+        ExampleObjectsJNI objectsNativeMethods = new ExampleObjectsJNI();
+        UserData userFromNative = objectsNativeMethods.createUser(name, balance);
+        assertNotNull(userFromNative);
+        assertEquals(userFromNative.name, name);
+        assertTrue(userFromNative.balance == balance);
+    }
+    
+    @Test
+    public void whenNativeCallingObjectMethod_thenResultIsAsExpected() {
+        String name = "Sergio Ramos";
+        double balance = 666.77;
+        ExampleObjectsJNI objectsNativeMethods = new ExampleObjectsJNI();
+        UserData userData = new UserData();
+        userData.name = name;
+        userData.balance = balance;
+        assertEquals(objectsNativeMethods.printUserData(userData), "[name]=" + name + ", [balance]=" + balance);
+    }
+    
+}

libraries-data/README.md

@@ -3,5 +3,9 @@
 - [Introduction to ORMLite](http://www.baeldung.com/ormlite)
 - [Introduction To Kryo](http://www.baeldung.com/kryo)
 - [Introduction to KafkaStreams in Java](http://www.baeldung.com/java-kafka-streams)
+- [Guide to Java Data Objects](http://www.baeldung.com/jdo)
+- [Intro to JDO Queries 2/2](http://www.baeldung.com/jdo-queries)
+- [Introduction to HikariCP](http://www.baeldung.com/hikaricp)
+- [Introduction to JCache](http://www.baeldung.com/jcache)
 - [A Guide to Apache Ignite](http://www.baeldung.com/apache-ignite)
-- [Apache Ignite with Spring Data](http://www.baeldung.com/apache-ignite-spring-data)
+- [Apache Ignite with Spring Data](http://www.baeldung.com/apache-ignite-spring-data)

libraries-data/log4j.properties

@@ -0,0 +1 @@
+log4j.rootLogger=INFO, stdout

libraries-data/myPersistence.xml

@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="UTF-8"?><root>
+    
+    
+    
+
+    
+    
+
+    
+    
+
+    
+    
+
+    
+    
+
+    
+    
+
+    
+    
+
+    
+    
+</root>

libraries-data/pom.xml

@@ -87,6 +87,60 @@
             <artifactId>gson</artifactId>
             <version>${gson.version}</version>
         </dependency>
+        <!-- Hikari  CP -->
+        <dependency>
+            <groupId>com.zaxxer</groupId>
+            <artifactId>HikariCP</artifactId>
+            <version>2.7.2</version>
+            <scope>compile</scope>
+        </dependency>
+        <!-- JDO -->
+        <dependency>
+            <groupId>org.datanucleus</groupId>
+            <artifactId>javax.jdo</artifactId>
+            <version>3.2.0-m7</version>
+        </dependency>
+        <dependency>
+            <groupId>org.datanucleus</groupId>
+            <artifactId>datanucleus-core</artifactId>
+            <version>5.1.1</version>
+        </dependency>
+        <dependency>
+            <groupId>org.datanucleus</groupId>
+            <artifactId>datanucleus-api-jdo</artifactId>
+            <version>5.1.1</version>
+        </dependency>
+        <dependency>
+            <groupId>org.datanucleus</groupId>
+            <artifactId>datanucleus-rdbms</artifactId>
+            <version>5.1.1</version>
+        </dependency>
+        <dependency>
+            <groupId>org.datanucleus</groupId>
+            <artifactId>datanucleus-maven-plugin</artifactId>
+            <version>5.0.2</version>
+        </dependency>
+        <dependency>
+            <groupId>org.datanucleus</groupId>
+            <artifactId>datanucleus-xml</artifactId>
+            <version>5.0.0-release</version>
+        </dependency>
+        <dependency>
+            <groupId>org.datanucleus</groupId>
+            <artifactId>datanucleus-jdo-query</artifactId>
+            <version>5.0.4</version>
+        </dependency>
+        <!-- Jcache -->
+        <dependency>
+            <groupId>javax.cache</groupId>
+            <artifactId>cache-api</artifactId>
+            <version>${cache.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.hazelcast</groupId>
+            <artifactId>hazelcast</artifactId>
+            <version>${hazelcast.version}</version>
+        </dependency>
     </dependencies>
 
     <build>
@@ -176,6 +230,29 @@
             </plugin>
             <!-- /Reladomo -->
 
+            <!-- JDO Plugin -->
+            <plugin>
+                <groupId>org.datanucleus</groupId>
+                <artifactId>datanucleus-maven-plugin</artifactId>
+                <version>5.0.2</version>
+                <configuration>
+                    <api>JDO</api>
+                    <props>${basedir}/datanucleus.properties</props>
+                    <log4jConfiguration>${basedir}/log4j.properties</log4jConfiguration>
+                    <verbose>true</verbose>
+                    <fork>false</fork>
+                    <!-- Solve windows line too long error -->
+                </configuration>
+                <executions>
+                    <execution>
+                        <phase>process-classes</phase>
+                        <goals>
+                            <goal>enhance</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+
         </plugins>
     </build>
 
@@ -196,8 +273,10 @@
         <kafka.version>1.0.0</kafka.version>
         <ignite.version>2.4.0</ignite.version>
         <gson.version>2.8.2</gson.version>
+        <cache.version>1.1.0</cache.version>
+        <hazelcast.version>3.8.4</hazelcast.version>     
         <maven-antrun-plugin.version>1.8</maven-antrun-plugin.version>
         <build-helper-maven-plugin.version>3.0.0</build-helper-maven-plugin.version>
     </properties>
 
-</project>
+</project>

libraries-data/src/main/java/com/baeldung/jdo/query/MyApp.java

@@ -1,96 +1,96 @@
-package com.baeldung.jdo.query;
+package com.baeldung.jdo.query;
-
+
-import java.util.List;
+import java.util.List;
-
+
-import javax.jdo.JDOQLTypedQuery;
+import javax.jdo.JDOQLTypedQuery;
-import javax.jdo.PersistenceManager;
+import javax.jdo.PersistenceManager;
-import javax.jdo.PersistenceManagerFactory;
+import javax.jdo.PersistenceManagerFactory;
-import javax.jdo.Query;
+import javax.jdo.Query;
-
+
-import org.datanucleus.api.jdo.JDOPersistenceManagerFactory;
+import org.datanucleus.api.jdo.JDOPersistenceManagerFactory;
-import org.datanucleus.metadata.PersistenceUnitMetaData;
+import org.datanucleus.metadata.PersistenceUnitMetaData;
-
+
-public class MyApp {
+public class MyApp {
-
+
-    private static PersistenceManagerFactory pmf;
+    private static PersistenceManagerFactory pmf;
-    private static PersistenceManager pm;
+    private static PersistenceManager pm;
-
+
-    public static void main(String[] args) {
+    public static void main(String[] args) {
-
+
-        defineDynamicPersistentUnit();
+        defineDynamicPersistentUnit();
-        createTestData();
+        createTestData();
-        queryUsingJDOQL();
+        queryUsingJDOQL();
-        queryUsingTypedJDOQL();
+        queryUsingTypedJDOQL();
-        queryUsingSQL();
+        queryUsingSQL();
-        queryUsingJPQL();
+        queryUsingJPQL();
-
+
-    }
+    }
-
+
-    public static void createTestData() {
+    public static void createTestData() {
-        ProductItem item1 = new ProductItem("supportedItem", "price less than 10", "SoldOut", 5);
+        ProductItem item1 = new ProductItem("supportedItem", "price less than 10", "SoldOut", 5);
-        ProductItem item2 = new ProductItem("pro2", "price less than 10", "InStock", 8);
+        ProductItem item2 = new ProductItem("pro2", "price less than 10", "InStock", 8);
-        ProductItem item3 = new ProductItem("pro3", "price more than 10", "SoldOut", 15);
+        ProductItem item3 = new ProductItem("pro3", "price more than 10", "SoldOut", 15);
-
+
-        if (pm != null) {
+        if (pm != null) {
-            pm.makePersistent(item1);
+            pm.makePersistent(item1);
-            pm.makePersistent(item2);
+            pm.makePersistent(item2);
-            pm.makePersistent(item3);
+            pm.makePersistent(item3);
-        }
+        }
-    }
+    }
-
+
-    public static void defineDynamicPersistentUnit() {
+    public static void defineDynamicPersistentUnit() {
-
+
-        PersistenceUnitMetaData pumd = new PersistenceUnitMetaData("dynamic-unit", "RESOURCE_LOCAL", null);
+        PersistenceUnitMetaData pumd = new PersistenceUnitMetaData("dynamic-unit", "RESOURCE_LOCAL", null);
-        pumd.addProperty("javax.jdo.option.ConnectionURL", "jdbc:mysql://localhost:3306/jdo_db");
+        pumd.addProperty("javax.jdo.option.ConnectionURL", "jdbc:mysql://localhost:3306/jdo_db");
-        pumd.addProperty("javax.jdo.option.ConnectionUserName", "root");
+        pumd.addProperty("javax.jdo.option.ConnectionUserName", "root");
-        pumd.addProperty("javax.jdo.option.ConnectionPassword", "admin");
+        pumd.addProperty("javax.jdo.option.ConnectionPassword", "admin");
-        pumd.addProperty("javax.jdo.option.ConnectionDriverName", "com.mysql.jdbc.Driver");
+        pumd.addProperty("javax.jdo.option.ConnectionDriverName", "com.mysql.jdbc.Driver");
-        pumd.addProperty("datanucleus.schema.autoCreateAll", "true");
+        pumd.addProperty("datanucleus.schema.autoCreateAll", "true");
-
+
-        pmf = new JDOPersistenceManagerFactory(pumd, null);
+        pmf = new JDOPersistenceManagerFactory(pumd, null);
-        pm = pmf.getPersistenceManager();
+        pm = pmf.getPersistenceManager();
-    }
+    }
-
+
-    public static void queryUsingJDOQL() {
+    public static void queryUsingJDOQL() {
-
+
-        Query query = pm.newQuery("SELECT FROM com.baeldung.jdo.query.ProductItem " + "WHERE price < threshold PARAMETERS double threshold");
+        Query query = pm.newQuery("SELECT FROM com.baeldung.jdo.query.ProductItem " + "WHERE price < threshold PARAMETERS double threshold");
-        List<ProductItem> explicitParamResults = (List<ProductItem>) query.execute(10);
+        List<ProductItem> explicitParamResults = (List<ProductItem>) query.execute(10);
-
+
-        query = pm.newQuery("SELECT FROM " + "com.baeldung.jdo.query.ProductItem WHERE price < :threshold");
+        query = pm.newQuery("SELECT FROM " + "com.baeldung.jdo.query.ProductItem WHERE price < :threshold");
-        query.setParameters("double threshold");
+        query.setParameters("double threshold");
-        List<ProductItem> explicitParamResults2 = (List<ProductItem>) query.execute(10);
+        List<ProductItem> explicitParamResults2 = (List<ProductItem>) query.execute(10);
-
+
-        query = pm.newQuery("SELECT FROM " + "com.baeldung.jdo.query.ProductItem WHERE price < :threshold");
+        query = pm.newQuery("SELECT FROM " + "com.baeldung.jdo.query.ProductItem WHERE price < :threshold");
-        List<ProductItem> implicitParamResults = (List<ProductItem>) query.execute(10);
+        List<ProductItem> implicitParamResults = (List<ProductItem>) query.execute(10);
-
+
-    }
+    }
-
+
-    public static void queryUsingTypedJDOQL() {
+    public static void queryUsingTypedJDOQL() {
-        JDOQLTypedQuery<ProductItem> tq = pm.newJDOQLTypedQuery(ProductItem.class);
+        JDOQLTypedQuery<ProductItem> tq = pm.newJDOQLTypedQuery(ProductItem.class);
-        QProductItem cand = QProductItem.candidate();
+        QProductItem cand = QProductItem.candidate();
-        tq = tq.filter(cand.price.lt(10).and(cand.name.startsWith("pro")));
+        tq = tq.filter(cand.price.lt(10).and(cand.name.startsWith("pro")));
-        List<ProductItem> results = tq.executeList();
+        List<ProductItem> results = tq.executeList();
-
+
-    }
+    }
-
+
-    public static void queryUsingSQL() {
+    public static void queryUsingSQL() {
-
+
-        Query query = pm.newQuery("javax.jdo.query.SQL", "select * from " + "product_item where price < ? and status = ?");
+        Query query = pm.newQuery("javax.jdo.query.SQL", "select * from " + "product_item where price < ? and status = ?");
-        query.setClass(ProductItem.class);
+        query.setClass(ProductItem.class);
-        query.setParameters(10, "InStock");
+        query.setParameters(10, "InStock");
-        List<ProductItem> results = query.executeList();
+        List<ProductItem> results = query.executeList();
-
+
-    }
+    }
-
+
-    public static void queryUsingJPQL() {
+    public static void queryUsingJPQL() {
-        Query query = pm.newQuery("JPQL", "select i from " + "com.baeldung.jdo.query.ProductItem i where i.price < 10" + " and i.status = 'InStock'");
+        Query query = pm.newQuery("JPQL", "select i from " + "com.baeldung.jdo.query.ProductItem i where i.price < 10" + " and i.status = 'InStock'");
-        List<ProductItem> results = (List<ProductItem>) query.execute();
+        List<ProductItem> results = (List<ProductItem>) query.execute();
-
+
-    }
+    }
-
+
-    public static void namedQuery() {
+    public static void namedQuery() {
-        Query<ProductItem> query = pm.newNamedQuery(ProductItem.class, "PriceBelow10");
+        Query<ProductItem> query = pm.newNamedQuery(ProductItem.class, "PriceBelow10");
-        List<ProductItem> results = query.executeList();
+        List<ProductItem> results = query.executeList();
-
+
-    }
+    }
-}
+}

libraries-data/src/main/java/com/baeldung/jdo/query/ProductItem.java

@@ -1,70 +1,70 @@
-package com.baeldung.jdo.query;
+package com.baeldung.jdo.query;
-
+
-import javax.jdo.annotations.IdGeneratorStrategy;
+import javax.jdo.annotations.IdGeneratorStrategy;
-import javax.jdo.annotations.PersistenceCapable;
+import javax.jdo.annotations.PersistenceCapable;
-import javax.jdo.annotations.Persistent;
+import javax.jdo.annotations.Persistent;
-import javax.jdo.annotations.PrimaryKey;
+import javax.jdo.annotations.PrimaryKey;
-
+
-@PersistenceCapable(table = "product_item")
+@PersistenceCapable(table = "product_item")
-public class ProductItem {
+public class ProductItem {
-
+
-    @PrimaryKey
+    @PrimaryKey
-    @Persistent(valueStrategy = IdGeneratorStrategy.INCREMENT)
+    @Persistent(valueStrategy = IdGeneratorStrategy.INCREMENT)
-    int id;
+    int id;
-    String name;
+    String name;
-    String description;
+    String description;
-    String status;
+    String status;
-    double price;
+    double price;
-
+
-    public ProductItem() {
+    public ProductItem() {
-
+
-    }
+    }
-
+
-    public ProductItem(String name, String description, String status, double price) {
+    public ProductItem(String name, String description, String status, double price) {
-        this.name = name;
+        this.name = name;
-        this.description = description;
+        this.description = description;
-        this.status = status;
+        this.status = status;
-        this.price = price;
+        this.price = price;
-    }
+    }
-
+
-    public int getId() {
+    public int getId() {
-        return id;
+        return id;
-    }
+    }
-
+
-    public void setId(int id) {
+    public void setId(int id) {
-        this.id = id;
+        this.id = id;
-    }
+    }
-
+
-    public String getName() {
+    public String getName() {
-        return name;
+        return name;
-    }
+    }
-
+
-    public void setName(String name) {
+    public void setName(String name) {
-        this.name = name;
+        this.name = name;
-    }
+    }
-
+
-    public String getDescription() {
+    public String getDescription() {
-        return description;
+        return description;
-    }
+    }
-
+
-    public void setDescription(String description) {
+    public void setDescription(String description) {
-        this.description = description;
+        this.description = description;
-    }
+    }
-
+
-    public double getPrice() {
+    public double getPrice() {
-        return price;
+        return price;
-    }
+    }
-
+
-    public void setPrice(double price) {
+    public void setPrice(double price) {
-        this.price = price;
+        this.price = price;
-    }
+    }
-
+
-    public String getStatus() {
+    public String getStatus() {
-        return status;
+        return status;
-    }
+    }
-
+
-    public void setStatus(String status) {
+    public void setStatus(String status) {
-        this.status = status;
+        this.status = status;
-    }
+    }
-
+
-}
+}

libraries-data/src/main/java/com/baeldung/jdo/xml/AnnotadedPerson.java

@@ -1,66 +1,66 @@
-package com.baeldung.jdo.xml;
+package com.baeldung.jdo.xml;
-
+
-import java.util.ArrayList;
+import java.util.ArrayList;
-import java.util.List;
+import java.util.List;
-
+
-import javax.jdo.annotations.Element;
+import javax.jdo.annotations.Element;
-import javax.jdo.annotations.PersistenceCapable;
+import javax.jdo.annotations.PersistenceCapable;
-import javax.jdo.annotations.PrimaryKey;
+import javax.jdo.annotations.PrimaryKey;
-import javax.xml.bind.annotation.XmlAttribute;
+import javax.xml.bind.annotation.XmlAttribute;
-import javax.xml.bind.annotation.XmlElement;
+import javax.xml.bind.annotation.XmlElement;
-import javax.xml.bind.annotation.XmlElementWrapper;
+import javax.xml.bind.annotation.XmlElementWrapper;
-
+
-@PersistenceCapable(schema = "/myproduct/people", table = "person")
+@PersistenceCapable(schema = "/myproduct/people", table = "person")
-public class AnnotadedPerson {
+public class AnnotadedPerson {
-    @XmlAttribute
+    @XmlAttribute
-    private long personNum;
+    private long personNum;
-
+
-    @PrimaryKey
+    @PrimaryKey
-    private String firstName;
+    private String firstName;
-    private String lastName;
+    private String lastName;
-
+
-    @XmlElementWrapper(name = "phone-numbers")
+    @XmlElementWrapper(name = "phone-numbers")
-    @XmlElement(name = "phone-number")
+    @XmlElement(name = "phone-number")
-    @Element(types = String.class)
+    @Element(types = String.class)
-    private List phoneNumbers = new ArrayList();
+    private List phoneNumbers = new ArrayList();
-
+
-    public AnnotadedPerson(long personNum, String firstName, String lastName) {
+    public AnnotadedPerson(long personNum, String firstName, String lastName) {
-        super();
+        super();
-        this.personNum = personNum;
+        this.personNum = personNum;
-        this.firstName = firstName;
+        this.firstName = firstName;
-        this.lastName = lastName;
+        this.lastName = lastName;
-    }
+    }
-
+
-    public long getPersonNum() {
+    public long getPersonNum() {
-        return personNum;
+        return personNum;
-    }
+    }
-
+
-    public void setPersonNum(long personNum) {
+    public void setPersonNum(long personNum) {
-        this.personNum = personNum;
+        this.personNum = personNum;
-    }
+    }
-
+
-    public String getFirstName() {
+    public String getFirstName() {
-        return firstName;
+        return firstName;
-    }
+    }
-
+
-    public void setFirstName(String firstName) {
+    public void setFirstName(String firstName) {
-        this.firstName = firstName;
+        this.firstName = firstName;
-    }
+    }
-
+
-    public String getLastName() {
+    public String getLastName() {
-        return lastName;
+        return lastName;
-    }
+    }
-
+
-    public void setLastName(String lastName) {
+    public void setLastName(String lastName) {
-        this.lastName = lastName;
+        this.lastName = lastName;
-    }
+    }
-
+
-    public List getPhoneNumbers() {
+    public List getPhoneNumbers() {
-        return phoneNumbers;
+        return phoneNumbers;
-    }
+    }
-
+
-    public void setPhoneNumbers(List phoneNumbers) {
+    public void setPhoneNumbers(List phoneNumbers) {
-        this.phoneNumbers = phoneNumbers;
+        this.phoneNumbers = phoneNumbers;
-    }
+    }
-
+
-}
+}

libraries-data/src/main/java/com/baeldung/jdo/xml/MyApp.java

@@ -1,105 +1,105 @@
-package com.baeldung.jdo.xml;
+package com.baeldung.jdo.xml;
-
+
-import java.util.List;
+import java.util.List;
-
+
-import javax.jdo.JDOHelper;
+import javax.jdo.JDOHelper;
-import javax.jdo.PersistenceManager;
+import javax.jdo.PersistenceManager;
-import javax.jdo.PersistenceManagerFactory;
+import javax.jdo.PersistenceManagerFactory;
-import javax.jdo.Query;
+import javax.jdo.Query;
-import javax.jdo.Transaction;
+import javax.jdo.Transaction;
-
+
-import org.datanucleus.api.jdo.JDOPersistenceManagerFactory;
+import org.datanucleus.api.jdo.JDOPersistenceManagerFactory;
-import org.datanucleus.metadata.PersistenceUnitMetaData;
+import org.datanucleus.metadata.PersistenceUnitMetaData;
-
+
-public class MyApp {
+public class MyApp {
-
+
-    private static PersistenceUnitMetaData pumd;
+    private static PersistenceUnitMetaData pumd;
-    private static PersistenceManagerFactory pmf;
+    private static PersistenceManagerFactory pmf;
-    private static PersistenceManager pm;
+    private static PersistenceManager pm;
-
+
-    public static void main(String[] args) {
+    public static void main(String[] args) {
-
+
-        // persist product object using dynamic persistence unit
+        // persist product object using dynamic persistence unit
-        defineDynamicPersistentUnit();
+        defineDynamicPersistentUnit();
-        Product product = new Product("id1", "Sony Discman", "A standard discman from Sony", 49.99);
+        Product product = new Product("id1", "Sony Discman", "A standard discman from Sony", 49.99);
-        persistObject(product);
+        persistObject(product);
-        closePersistenceManager();
+        closePersistenceManager();
-
+
-        // persist AnnotatedPerson object using named pmf
+        // persist AnnotatedPerson object using named pmf
-        defineNamedPersistenceManagerFactory("XmlDatastore");
+        defineNamedPersistenceManagerFactory("XmlDatastore");
-        AnnotadedPerson annotatedPerson = new AnnotadedPerson(654320, "annotated", "person");
+        AnnotadedPerson annotatedPerson = new AnnotadedPerson(654320, "annotated", "person");
-        annotatedPerson.getPhoneNumbers().add("999999999");
+        annotatedPerson.getPhoneNumbers().add("999999999");
-        annotatedPerson.getPhoneNumbers().add("000000000");
+        annotatedPerson.getPhoneNumbers().add("000000000");
-        persistObject(annotatedPerson);
+        persistObject(annotatedPerson);
-        queryAnnotatedPersonsInXML();
+        queryAnnotatedPersonsInXML();
-        closePersistenceManager();
+        closePersistenceManager();
-
+
-        // persist Person object using PMF created by properties file
+        // persist Person object using PMF created by properties file
-        definePersistenceManagerFactoryUsingPropertiesFile("META-INF\\datanucleus.properties");
+        definePersistenceManagerFactoryUsingPropertiesFile("META-INF\\datanucleus.properties");
-        Person person = new Person(654321, "bealdung", "author");
+        Person person = new Person(654321, "bealdung", "author");
-        person.getPhoneNumbers().add("123456789");
+        person.getPhoneNumbers().add("123456789");
-        person.getPhoneNumbers().add("987654321");
+        person.getPhoneNumbers().add("987654321");
-        persistObject(person);
+        persistObject(person);
-        queryPersonsInXML();
+        queryPersonsInXML();
-        closePersistenceManager();
+        closePersistenceManager();
-    }
+    }
-
+
-    public static void defineDynamicPersistentUnit() {
+    public static void defineDynamicPersistentUnit() {
-
+
-        PersistenceUnitMetaData pumd = new PersistenceUnitMetaData("dynamic-unit", "RESOURCE_LOCAL", null);
+        PersistenceUnitMetaData pumd = new PersistenceUnitMetaData("dynamic-unit", "RESOURCE_LOCAL", null);
-        pumd.addProperty("javax.jdo.option.ConnectionURL", "xml:file:myfile_dynamicPMF.xml");
+        pumd.addProperty("javax.jdo.option.ConnectionURL", "xml:file:myfile_dynamicPMF.xml");
-        pumd.addProperty("datanucleus.schema.autoCreateAll", "true");
+        pumd.addProperty("datanucleus.schema.autoCreateAll", "true");
-        pumd.addProperty("datanucleus.xml.indentSize", "4");
+        pumd.addProperty("datanucleus.xml.indentSize", "4");
-
+
-        pmf = new JDOPersistenceManagerFactory(pumd, null);
+        pmf = new JDOPersistenceManagerFactory(pumd, null);
-        pm = pmf.getPersistenceManager();
+        pm = pmf.getPersistenceManager();
-    }
+    }
-
+
-    public static void defineNamedPersistenceManagerFactory(String pmfName) {
+    public static void defineNamedPersistenceManagerFactory(String pmfName) {
-
+
-        pmf = JDOHelper.getPersistenceManagerFactory("XmlDatastore");
+        pmf = JDOHelper.getPersistenceManagerFactory("XmlDatastore");
-        pm = pmf.getPersistenceManager();
+        pm = pmf.getPersistenceManager();
-    }
+    }
-
+
-    public static void definePersistenceManagerFactoryUsingPropertiesFile(String filePath) {
+    public static void definePersistenceManagerFactoryUsingPropertiesFile(String filePath) {
-
+
-        pmf = JDOHelper.getPersistenceManagerFactory(filePath);
+        pmf = JDOHelper.getPersistenceManagerFactory(filePath);
-        pm = pmf.getPersistenceManager();
+        pm = pmf.getPersistenceManager();
-    }
+    }
-
+
-    public static void closePersistenceManager() {
+    public static void closePersistenceManager() {
-
+
-        if (pm != null && !pm.isClosed()) {
+        if (pm != null && !pm.isClosed()) {
-            pm.close();
+            pm.close();
-        }
+        }
-    }
+    }
-
+
-    public static void persistObject(Object obj) {
+    public static void persistObject(Object obj) {
-
+
-        Transaction tx = pm.currentTransaction();
+        Transaction tx = pm.currentTransaction();
-
+
-        try {
+        try {
-            tx.begin();
+            tx.begin();
-            pm.makePersistent(obj);
+            pm.makePersistent(obj);
-            tx.commit();
+            tx.commit();
-        } finally {
+        } finally {
-            if (tx.isActive()) {
+            if (tx.isActive()) {
-                tx.rollback();
+                tx.rollback();
-            }
+            }
-        }
+        }
-    }
+    }
-
+
-    public static void queryPersonsInXML() {
+    public static void queryPersonsInXML() {
-
+
-        Query<Person> query = pm.newQuery(Person.class);
+        Query<Person> query = pm.newQuery(Person.class);
-        List<Person> result = query.executeList();
+        List<Person> result = query.executeList();
-        System.out.println("name: " + result.get(0).getFirstName());
+        System.out.println("name: " + result.get(0).getFirstName());
-    }
+    }
-
+
-    public static void queryAnnotatedPersonsInXML() {
+    public static void queryAnnotatedPersonsInXML() {
-
+
-        Query<AnnotadedPerson> query = pm.newQuery(AnnotadedPerson.class);
+        Query<AnnotadedPerson> query = pm.newQuery(AnnotadedPerson.class);
-        List<AnnotadedPerson> result = query.executeList();
+        List<AnnotadedPerson> result = query.executeList();
-        System.out.println("name: " + result.get(0).getFirstName());
+        System.out.println("name: " + result.get(0).getFirstName());
-    }
+    }
-}
+}

libraries-data/src/main/java/com/baeldung/jdo/xml/Person.java

@@ -1,58 +1,58 @@
-package com.baeldung.jdo.xml;
+package com.baeldung.jdo.xml;
-
+
-import java.util.ArrayList;
+import java.util.ArrayList;
-import java.util.List;
+import java.util.List;
-
+
-import javax.jdo.annotations.PersistenceCapable;
+import javax.jdo.annotations.PersistenceCapable;
-import javax.jdo.annotations.PrimaryKey;
+import javax.jdo.annotations.PrimaryKey;
-
+
-@PersistenceCapable
+@PersistenceCapable
-public class Person {
+public class Person {
-    private long personNum;
+    private long personNum;
-
+
-    @PrimaryKey
+    @PrimaryKey
-    private String firstName;
+    private String firstName;
-    private String lastName;
+    private String lastName;
-
+
-    private List phoneNumbers = new ArrayList();
+    private List phoneNumbers = new ArrayList();
-
+
-    public Person(long personNum, String firstName, String lastName) {
+    public Person(long personNum, String firstName, String lastName) {
-        super();
+        super();
-        this.personNum = personNum;
+        this.personNum = personNum;
-        this.firstName = firstName;
+        this.firstName = firstName;
-        this.lastName = lastName;
+        this.lastName = lastName;
-    }
+    }
-
+
-    public long getPersonNum() {
+    public long getPersonNum() {
-        return personNum;
+        return personNum;
-    }
+    }
-
+
-    public void setPersonNum(long personNum) {
+    public void setPersonNum(long personNum) {
-        this.personNum = personNum;
+        this.personNum = personNum;
-    }
+    }
-
+
-    public String getFirstName() {
+    public String getFirstName() {
-        return firstName;
+        return firstName;
-    }
+    }
-
+
-    public void setFirstName(String firstName) {
+    public void setFirstName(String firstName) {
-        this.firstName = firstName;
+        this.firstName = firstName;
-    }
+    }
-
+
-    public String getLastName() {
+    public String getLastName() {
-        return lastName;
+        return lastName;
-    }
+    }
-
+
-    public void setLastName(String lastName) {
+    public void setLastName(String lastName) {
-        this.lastName = lastName;
+        this.lastName = lastName;
-    }
+    }
-
+
-    public List getPhoneNumbers() {
+    public List getPhoneNumbers() {
-        return phoneNumbers;
+        return phoneNumbers;
-    }
+    }
-
+
-    public void setPhoneNumbers(List phoneNumbers) {
+    public void setPhoneNumbers(List phoneNumbers) {
-        this.phoneNumbers = phoneNumbers;
+        this.phoneNumbers = phoneNumbers;
-    }
+    }
-
+
-}
+}

libraries-data/src/main/java/com/baeldung/jdo/xml/Product.java

@@ -1,58 +1,58 @@
-package com.baeldung.jdo.xml;
+package com.baeldung.jdo.xml;
-
+
-import javax.jdo.annotations.PersistenceCapable;
+import javax.jdo.annotations.PersistenceCapable;
-import javax.jdo.annotations.PrimaryKey;
+import javax.jdo.annotations.PrimaryKey;
-
+
-@PersistenceCapable
+@PersistenceCapable
-public class Product {
+public class Product {
-
+
-    @PrimaryKey
+    @PrimaryKey
-    String id;
+    String id;
-    String name;
+    String name;
-    String description;
+    String description;
-    double price;
+    double price;
-
+
-    public Product() {
+    public Product() {
-
+
-    }
+    }
-
+
-    public Product(String id, String name, String description, double price) {
+    public Product(String id, String name, String description, double price) {
-        this.id = id;
+        this.id = id;
-        this.name = name;
+        this.name = name;
-        this.description = description;
+        this.description = description;
-        this.price = price;
+        this.price = price;
-    }
+    }
-
+
-    public String getId() {
+    public String getId() {
-        return id;
+        return id;
-    }
+    }
-
+
-    public void setId(String id) {
+    public void setId(String id) {
-        this.id = id;
+        this.id = id;
-    }
+    }
-
+
-    public String getName() {
+    public String getName() {
-        return name;
+        return name;
-    }
+    }
-
+
-    public void setName(String name) {
+    public void setName(String name) {
-        this.name = name;
+        this.name = name;
-    }
+    }
-
+
-    public String getDescription() {
+    public String getDescription() {
-        return description;
+        return description;
-    }
+    }
-
+
-    public void setDescription(String description) {
+    public void setDescription(String description) {
-        this.description = description;
+        this.description = description;
-    }
+    }
-
+
-    public double getPrice() {
+    public double getPrice() {
-        return price;
+        return price;
-    }
+    }
-
+
-    public void setPrice(double price) {
+    public void setPrice(double price) {
-        this.price = price;
+        this.price = price;
-    }
+    }
-
+
-}
+}

libraries-data/src/main/resources/META-INF/datanucleus.properties

@@ -0,0 +1,4 @@
+javax.jdo.PersistenceManagerFactoryClass=org.datanucleus.api.jdo.JDOPersistenceManagerFactory
+javax.jdo.option.ConnectionURL= xml:file:myfile-ds.xml
+datanucleus.xml.indentSize=6
+datanucleus.schema.autoCreateAll=true

libraries-data/src/main/resources/META-INF/jdoconfig.xml

@@ -1,17 +1,17 @@
-<?xml version="1.0" encoding="UTF-8"?>
+<?xml version="1.0" encoding="UTF-8"?>
-<jdoconfig xmlns="http://xmlns.jcp.org/xml/ns/jdo/jdoconfig"
+<jdoconfig xmlns="http://xmlns.jcp.org/xml/ns/jdo/jdoconfig"
-    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-    xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/jdo/jdoconfig
+    xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/jdo/jdoconfig
-        http://xmlns.jcp.org/xml/ns/jdo/jdoconfig_3_2.xsd"
+        http://xmlns.jcp.org/xml/ns/jdo/jdoconfig_3_2.xsd"
-    version="3.2">
+    version="3.2">
-
+
-    <!-- Datastore Txn PMF -->
+    <!-- Datastore Txn PMF -->
-    <persistence-manager-factory name="XmlDatastore">
+    <persistence-manager-factory name="XmlDatastore">
-        <property name="javax.jdo.PersistenceManagerFactoryClass"
+        <property name="javax.jdo.PersistenceManagerFactoryClass"
-            value="org.datanucleus.api.jdo.JDOPersistenceManagerFactory" />
+            value="org.datanucleus.api.jdo.JDOPersistenceManagerFactory" />
-        <property name="javax.jdo.option.ConnectionURL" value="xml:file:namedPMF-ds.xml" />
+        <property name="javax.jdo.option.ConnectionURL" value="xml:file:namedPMF-ds.xml" />
-        <property name="datanucleus.xml.indentSize" value="6" />
+        <property name="datanucleus.xml.indentSize" value="6" />
-        <property name="datanucleus.schema.autoCreateAll"
+        <property name="datanucleus.schema.autoCreateAll"
-            value="true" />
+            value="true" />
-    </persistence-manager-factory>
+    </persistence-manager-factory>
 </jdoconfig>

libraries-data/src/main/resources/META-INF/package.jdo

@@ -1,29 +1,29 @@
-<jdo xmlns="http://xmlns.jcp.org/xml/ns/jdo/jdo" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+<jdo xmlns="http://xmlns.jcp.org/xml/ns/jdo/jdo" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-    xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/jdo/jdo http://xmlns.jcp.org/xml/ns/jdo/jdo_3_1.xsd"
+    xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/jdo/jdo http://xmlns.jcp.org/xml/ns/jdo/jdo_3_1.xsd"
-    version="3.1">
+    version="3.1">
-    <package name="com.baeldung.jdo.xml">
+    <package name="com.baeldung.jdo.xml">
-        <class name="Person" detachable="true" schema="/myproduct/people"
+        <class name="Person" detachable="true" schema="/myproduct/people"
-            table="person">
+            table="person">
-            <field name="personNum">
+            <field name="personNum">
-                <extension vendor-name="datanucleus" key="XmlAttribute"
+                <extension vendor-name="datanucleus" key="XmlAttribute"
-                    value="true" />
+                    value="true" />
-            </field>
+            </field>
-            <field name="firstName" primary-key="true" /> <!-- PK since JAXB requires String -->
+            <field name="firstName" primary-key="true" /> <!-- PK since JAXB requires String -->
-            <field name="lastName" />
+            <field name="lastName" />
-            <field name="phoneNumbers">
+            <field name="phoneNumbers">
-                <collection element-type="java.lang.String" />
+                <collection element-type="java.lang.String" />
-                <element column="phoneNumber" />
+                <element column="phoneNumber" />
-            </field>
+            </field>
-        </class>
+        </class>
-    </package>
+    </package>
-    <package name="com.baeldung.jdo.query">
+    <package name="com.baeldung.jdo.query">
-        <class name="ProductItem" detachable="true" table="product_item">
+        <class name="ProductItem" detachable="true" table="product_item">
- 
+ 
-            <query name="PriceBelow10" language="javax.jdo.query.SQL">
+            <query name="PriceBelow10" language="javax.jdo.query.SQL">
-            <![CDATA[SELECT * FROM PRODUCT_ITEM WHERE PRICE < 10
+            <![CDATA[SELECT * FROM PRODUCT_ITEM WHERE PRICE < 10
-            ]]></query>
+            ]]></query>
- 
+ 
-        </class>
+        </class>
-    </package>
+    </package>
-
+
 </jdo>

libraries-data/src/test/java/com/baeldung/jcache/CacheLoaderTest.java

@@ -21,7 +21,8 @@ public class CacheLoaderTest {
 
     @Before
     public void setup() {
-        CachingProvider cachingProvider = Caching.getCachingProvider();
+        // Adding fully qualified class name because of multiple Cache Provider (Ignite and Hazelcast)
+        CachingProvider cachingProvider = Caching.getCachingProvider("com.hazelcast.cache.HazelcastCachingProvider");
         CacheManager cacheManager = cachingProvider.getCacheManager();
         MutableConfiguration<Integer, String> config = new MutableConfiguration<Integer, String>().setReadThrough(true).setCacheLoaderFactory(new FactoryBuilder.SingletonFactory<>(new SimpleCacheLoader()));
         this.cache = cacheManager.createCache("SimpleCache", config);
@@ -29,7 +30,7 @@ public class CacheLoaderTest {
 
     @After
     public void tearDown() {
-        Caching.getCachingProvider().getCacheManager().destroyCache(CACHE_NAME);
+        Caching.getCachingProvider("com.hazelcast.cache.HazelcastCachingProvider").getCacheManager().destroyCache(CACHE_NAME);
     }
 
     @Test
@@ -39,4 +40,4 @@ public class CacheLoaderTest {
             assertEquals("fromCache" + i, value);
         }
     }
-}
+}